📚 Year 7 CIE Science: High-Frequency Topics & Common Mistakes | Year 7 CIE 科学：高频考点与易错题分析
In Year 7 CIE Science, students often perform well in practical activities but lose marks on written questions that demand precise terminology, clear explanations and the ability to interpret data. This article identifies the most frequently tested topics across Biology, Chemistry and Physics, alongside the typical errors that cost marks in exams. Understanding these patterns helps learners focus their revision, strengthen core concepts and develop the exam technique needed to turn good knowledge into top grades.
在 Year 7 CIE 科学课程中，许多学生在动手实验部分表现不错，却在需要准确术语、清晰解释和数据解读的书面题目上频频失分。本文梳理了生物、化学、物理三科中最高频的考察主题，同时分析考试中常见的失分错误。了解这些规律，可以帮助同学们更有针对性地复习，巩固核心概念，并培养将扎实的知识转化为高分的答题技巧。
1. Cells and Microscopes | 细胞与显微镜
Questions about plant and animal cells appear in almost every Year 7 exam. Students must be able to label the nucleus, cytoplasm, cell membrane, cell wall, chloroplasts and vacuole, and state the function of each. A classic mistake is confusing the cell wall with the cell membrane, or forgetting that chloroplasts are found only in plant cells. When labeling a diagram, always draw a straight line from the structure to the label, without arrowheads, and write neatly.
关于植物和动物细胞的问题几乎出现在每份 Year 7 试卷中。学生必须能够正确标注细胞核、细胞质、细胞膜、细胞壁、叶绿体和液泡，并说明各自的功能。一个典型错误是把细胞壁和细胞膜混淆，或者忘记叶绿体只存在于植物细胞中。在图表标注时，一定要从结构处画一条直线指向标签，不加箭头，并且书写工整。
Microscope skills are equally high-frequency. You' ve lens) and explain how to prepare a wet mount slide. Many learners lose marks by writing 'zoom' instead of 'magnification', or by describing how to 'look' down the microscope without mentioning coarse and fine focus knobs. Always use the terms 'stage', 'clips', 'cover slip' and 'methylene blue' or 'iodine solution' when describing staining.
显微镜技能同样是高频考点。学生需要计算总放大倍数（目镜倍数 × 物镜倍数），并解释如何制作临时装片。不少学习者因为把'放大'写成'变焦'，或者在描述观察步骤时没有提到粗准焦螺旋和细准焦螺旋而失分。在描述染色时，务必使用'载物台'、'压片夹'、'盖玻片'和'亚甲蓝'或'碘液'等术语。
A sneaky error appears in comparisons: 'All cells have a nucleus.' This is false for mature red blood cells, but at Year 7, it's safer to focus on the generalisation 'plant and animal cells have a nucleus' while noting that bacterial cells lack one. Stick to the syllabus to avoid unnecessary confusion.
一个容易踩坑的对比题是：'所有细胞都有细胞核'。这句话对成熟的红细胞来说是错误的，但在 Year 7 阶段，更稳妥的做法是记住'植物和动物细胞有细胞核'这一概括，同时知道细菌细胞没有细胞核。紧扣考纲，避免引入不必要的混淆。
2. States of Matter and the Particle Model | 物质状态与粒子模型
The particle model is a cornerstone of Year 7 chemistry. Examiners want you to explain properties of solids, liquids and gases in terms of particle arrangement, movement and energy. The most common exam pitfall is drawing particles as unevenly spaced circles or showing them static. Solids must have particles arranged in a regular, fixed pattern, locked together but vibrating; liquids must show particles touching but able to slide past one another; gases must have particles far apart and moving rapidly in all directions.
粒子模型是 Year 7 化学的基础。考官希望你从粒子的排列方式、运动状态和能量高低来解释固体、液体和气体的性质。最常见的答题陷阱是把粒子画成间距不等的圆圈或静止不动。画固体时，粒子必须呈规则且固定的排列，紧紧相靠但不断振动；液体粒子必须相互接触但能够彼此滑过；气体粒子必须彼此远离并向各个方向快速运动。
The processes of melting, freezing, boiling, condensation, sublimation and deposition are tested with precise definitions. Do not say 'it turns into water' when asked about condensation; say 'gas changes to liquid'. Many students also confuse evaporation with boiling. Evaporation occurs at the surface, at any temperature, whereas boiling takes place throughout the liquid at a specific boiling point.
熔化、凝固、沸腾、冷凝、升华和凝华这些过程都会以准确定义的形式进行考查。当问到冷凝时，不要说'变成水'，而要说'气体变为液体'。很多学生还混淆蒸发和沸腾：蒸发发生在液体表面、任何温度下都可以进行；沸腾则是在特定沸点下、整个液体内部同时发生的剧烈汽化。
Diffusion in liquids and gases is another favourite. Always link diffusion to the random movement of particles and say it is the net movement from an area of high concentration to low concentration. A common slip is stating that diffusion 'stops' once substances are evenly spread; instead, particles continue moving, but there is no net change. Use the term 'dynamic equilibrium' if you want to impress.
液体和气体中的扩散也是常考点。务必把扩散与粒子的无规则运动联系起来，并说明扩散是指粒子从高浓度区域向低浓度区域的净移动。一个常见口误是说物质均匀分布后扩散就'停止'了；实际上粒子仍在运动，只是不再发生净变化。如果能用上'动态平衡'这个术语，会令考官眼前一亮。
3. Forces and Motion | 力与运动
Year 7 physics introduces balanced and unbalanced forces, weight, friction and air resistance. Force diagrams must be drawn with arrows that touch the object, point in the correct direction, and have lengths roughly proportional to magnitude. A classic mistake is drawing a force arrow 'floating' near the object or forgetting to label the force (e.g. 'gravity', 'thrust', 'friction', 'normal contact force'). Always measure force in newtons (N).
Year 7 物理部分介绍了平衡力与不平衡力、重力、摩擦力和空气阻力等概念。力的示意图必须满足箭头接触物体、方向正确且长度大致与力的大小成比例。经典错误是把箭头画在物体旁边'飘着'，或者忘记标注力的名称（例如'重力'、'推力'、'摩擦力'、'支持力'）。力的单位永远是牛顿（N）。
Calculating speed is a high-frequency number task. Use speed = distance ÷ time. The biggest trap is unit mismatch: if distance is in metres and time in seconds, speed is m/s; if time is in hours, speed is km/h or m/h. Always show your working, and convert units before calculating if necessary. Questions that provide a distance-time graph often ask for the speed over a particular segment; pick the correct change in distance and change in time, and check that the graph is a straight line for that segment (constant speed).
速度计算是高频数字题。使用公式 速度 = 距离 ÷ 时间。最大的陷阱是单位不匹配：如果距离用米、时间用秒，速度就是 m/s；如果时间用小时，速度就是 km/h 或 m/h。一定要写计算过程，必要时先转换单位再计算。有时题目给出距离-时间图，要求计算某一段的速度；要选取相应的距离变化和时间变化，并确认该段图线是直线（匀速）。
forces are balanced, and the object moves at a constant speed or stays still (it does not 'have no forces'). Many students incorrectly think 'no movement = no forces' ce acting upwards, even when stationary. Understanding this helps with free-body diagrams.
相对运动和平衡力也容易混淆。当两个大小相等、方向相反的力作用在物体上时，力是平衡的，物体保持匀速直线运动或静止（并非'没有力'）。很多学生错误地认为'不动就没有力'。实际上地球上任何物体都受到向下的重力和向上的支持力，即使静止不动也一样。理解这一点对画受力分析图很有帮助。
4. Acids, Alkalis and pH | 酸、碱与pH值
Identifying acids and alkalis using indicators is a core practical skill. Litmus paper turns red in acid, blue in alkali; universal indicator gives a spectrum of colours from red (pH 1-2) through green (neutral, pH 7) to purple (pH 13-14). A frequent error is stating that neutralisation produces water and salt but forgetting to name the specific salt. For hydrochloric acid + sodium hydroxide, the salt is sodium chloride. Always read the question carefully: if you are given the acid and alkali, you can work out the salt.
用指示剂识别酸和碱是一项核心实验技能。石蕊试纸遇酸变红、遇碱变蓝；通用指示剂呈现从红（pH 1-2）到绿（中性，pH 7）再到紫（pH 13-14）的颜色变化。一个常见错误是说中和反应生成水和盐，却忘记写出具体的盐的名称。例如盐酸 + 氢氧化钠，生成的盐是氯化钠。一定要仔细读题：如果试卷给出了酸和碱，你就能推导出盐的名称。
The pH scale is logarithmic: a solution of pH 4 is ten times more acidic than pH 5, but a hundred times more acidic than pH 6. This is a frequent trick in multiple-choice questions. Also, corrosive and irritant are hazard symbols you must recognise. If a question asks for a safety precaution, do not just say 'wear goggles'; specify that you should wear safety goggles to protect the eyes from splashes of acid or alkali.
pH 值是对数尺度：pH 4 的溶液酸性是 pH 5 的 10 倍，是 pH 6 的 100 倍。这是选择题中常见的陷阱。此外，你还需认识腐蚀性和刺激性等危险标志。如果题目要求写出安全预防措施，不要只说'戴护目镜'，而要写明'佩戴安全护目镜，防止酸液或碱液飞溅入眼'。
Laboratory preparation of acids and indicators may also come up. Remember that many household substances are acidic (vinegar, lemon juice) or alkaline (baking soda, soap). When planning an investigation to test unknown substances, you must include a control variable such as the volume of indicator used or the number of drops. Marks are often lost when students rush to write a 'method' but forget fair testing.
实验室制备酸和指示剂的方法也可能考到。要记住很多家庭用品是酸性的（醋、柠檬汁）或碱性的（小苏打、肥皂）。在规划一项测试未知物质的探究实验时，必须设定控制变量，比如指示剂的体积或滴数。许多学生在匆忙写'方法'时忘记公平测试，从而导致失分。
5. Plant Reproduction and Pollination | 植物繁殖与传粉
Flower structure is a visual topic that often carries many marks. Be able to label the petals, sepal, stamen (anther + filament) and carpel/pistil (stigma, style, ovary, ovules). An extremely common mistake is confusing the stamen (male part) with the carpel (female part) or mixing up anther and stigma. Use mnemonics: 'Stamen has a MAN inside' or 'Stigma is sticky to catch pollen'.
花的结构是一个考查图示的考点，通常分值不低。你需要会标注花瓣、萼片、雄蕊（花药 + 花丝）和雌蕊（柱头、花柱、子房、胚珠）。一个极其常见的错误是混淆雄蕊（雄性部分）与雌蕊（雌性部分），或者弄混花药和柱头。可以用顺口溜帮助记忆：'雄蕊有男子（stamen，类似 man），柱头有粘性'。
Pollination and fertilisation are not the same. Pollination is the transfer of pollen from anther to stigma (by wind, insects, etc.); fertilisation is the fusion of the male gamete (pollen nucleus) with the female gamete (ovum, inside the ovule). Writing 'fertilisation occurs when pollen lands on the stigma' will lose marks. After fertilisation, the ovary develops into fruit, and the ovules develop into seeds.
传粉和受精不是一回事。传粉是花粉从花药传到柱头的过程（借风、昆虫等媒介）；受精则是雄配子（花粉管中的精核）与胚珠内的卵细胞结合。如果写'花粉落到柱头上就是受精'，一定会扣分。受精后，子房发育成果实，胚珠发育成种子。
Seed dispersal adaptations are frequently tested. At Year 7, be ready to explain how structures such as wings, parachutes, hooks and fleshy fruits help dispersal by wind or animals. A point often missed is that the advantage of seed dispersal is to reduce competition for light, water and nutrients with the parent plant. Always link the adaptation to its advantage—not just 'it has hooks' but 'hooks attach to animal fur, carrying seeds away'.
种子传播的适应性结构也是常见考题。在 Year 7 阶段，你需要解释翅、降落伞状毛、钩刺和多汁果实等结构如何帮助植物借助风或动物传播。一个经常被忽略的得分点是说明种子传播的优势在于减少与母株竞争光、水和养分。一定要把结构与优势联系起来，不要只说'它有钩刺'，而要写'钩刺能附着在动物毛皮上，将种子携带到远处'。
6. Electrical Circuits | 电路
Year 7 circuit questions demand correct drawing of components using standard symbols, and the ability to describe series and parallel circuits. The most common diagram mistake is drawing the wires as curved or overlapping in a messy way, or showing a short circuit by connecting a wire directly across the battery without a component. Use a ruler and try to draw rectangular loops with components on each side.
Year 7 的电路题会要求用标准符号正确画出元件，并能描述串联和并联电路。最常见的绘图错误是把导线画成弯曲的乱七八糟的线，或者画出将导线直接跨接在电池两端却没有任何元件的短路电路。要用直尺画图，并尽量画出矩形回路，每个边上放置元件。
Current is measured in amperes (A) using an ammeter connected in series; potential difference (voltage) is measured in volts (V) using a voltmeter connected in parallel. Many learners lose marks by placing the ammeter parallel to the component or the voltmeter in series. Remember the mnemonic: 'Ammeter is Always in series; Voltmeter is in parallel (to measure Voltage)'.
电流以安培（A）为单位，用串联的安培表测量；电压（电势差）以伏特（V）为单位，用并联的伏特表测量。许多学生因为把安培表并联在元件两端，或把伏特表串联在电路中而丢分。记住口诀：'测电流，表串联；测电压，表并联'。
In a series circuit, current is the same everywhere, and the battery voltage is shared between components. In a parallel circuit, voltage across each branch equals the battery voltage, and currents split at junctions and recombine. Data interpretation questions often provide ammeter readings; check if the components are identical or different to predict how current is shared.
在串联电路中，各处电流相等，电源电压在元件之间分配。在并联电路中，各支路两端的电压等于电源电压，电流在节点处分流、在回汇处合并。数据分析题常常给出多个安培表读数；需要判断各元件是否相同，以预测电流的分配方式。
7. Energy Resources and Energy Transfers | 能源与能量转移
Renewable and non-renewable energy resources are a guaranteed topic. Solar, wind, wave, tidal, hydroelectric, geothermal and biomass are renewable; fossil fuels (coal, oil, natural gas) and nuclear fuels are non-renewable. Do not just memorise the names—be able to describe how each generates electricity. A common weak spot is confusing tidal (rising and falling of sea level, very predictable) with wave (wind-driven surface motion, less predictable).
可再生能源与不可再生能源是必考内容。太阳能、风能、波浪能、潮汐能、水力发电、地热能和生物质能属于可再生能源；化石燃料（煤、石油、天然气）和核燃料属于不可再生能源。不要只背名称，而要能描述每种能源的发电原理。一个常见薄弱点是混淆潮汐能（海水周期性涨落，高度可预测）和波浪能（由风引起的海面运动，较难预测）。
input energy → (device) → useful output energy + wasted energy (often heat). Do not write 'energy is lost'. Energy is never destroyed, only transferred or dissipated as 'wasted' energy, typically heat and sound. The word 'dissipated' is preferred in CIE mark schemes.
能量转移可以用能量转移链或框图表示，格式为：输入能量 → （装置）→ 有用的输出能量 + 浪费的能量（通常是热）。不要写'能量丢失'。能量不会凭空消失，只会转移或耗散为'浪费'的能量，通常是热能和声能。CIE 评分方案中强烈推荐使用'耗散（dissipated）'一词。
Sankey diagrams appear in higher-level questions but may be introduced in Year 7 as extension. They show energy input, useful output and wasted output as arrows of proportional width. If given a Sankey diagram, you might be asked to calculate efficiency: efficiency = (useful energy output ÷ total energy input) × 100%. This is a number skill where marks are lost through incorrect unit conversion or missing the percentage symbol.
桑基图一般出现在高年级拓展题中，但 Year 7 也可能作为拔高题引入。桑基图用箭头宽度表示能量输入、有用输出和浪费输出。如果给出桑基图，可能会要求计算效率：效率 =（有用的能量输出 ÷ 总能量输入）× 100%。这是一道数字题，学生常因单位转换错误或漏写百分号而丢分。
8. Variation, Classification and Adaptations | 变异、分类与适应性
Living organisms are classified into kingdoms (animals, plants, fungi, prokaryotes, protoctists). At Year 7, the focus is on vertebrates and invertebrates. The five vertebrate groups—mammals, birds, reptiles, amphibians and fish—must be linked to characteristics: body covering, breathing organs, reproduction method and thermoregulation. A typical error is saying "amphibians have moist skin and live in water"—they live both in water and on land, and their skin must stay moist for respiration.
生物按界划分为动物界、植物界、真菌界、原核生物界和原生生物界。在 Year 7 阶段，重点在于脊椎动物和无脊椎动物。五大脊椎动物类群——哺乳类、鸟类、爬行类、两栖类和鱼类——必须联系其身体被覆、呼吸器官、繁殖方式和体温调节特征。一个典型的错误是说'两栖动物有湿润皮肤，生活在水中'——实际上它们水陆两栖，皮肤必须保持湿润以辅助呼吸。
Adaptations to habitat are examined through examples such as camel (desert), polar bear (Arctic) and cactus (dry environment). Always use the language 'structural adaptation', 'behavioural adaptation' or 'functional adaptation' where possible. For instance, a camel's hump is a structural adaptation storing fat (not water!); producing concentrated urine is a functional adaptation to reduce water loss. If you state the hump stores water, you lose the mark.
动物对栖息地的适应常以骆驼（沙漠）、北极熊（北极）和仙人掌（干旱环境）等例子考查。尽量使用'结构适应'、'行为适应'或'功能适应'等术语。例如，骆驼的驼峰是存贮脂肪（不是水！）的结构适应；排出浓缩的尿液是减少水分流失的功能适应。如果答成'驼峰存水'，就会扣分。
Continuous and discontinuous variation is another favourite. Height and weight are continuous (range of values), while eye colour, blood group and tongue rolling are discontinuous (distinct categories). Students often lose marks plotting bar charts for continuous data; continuous data should be plotted as a histogram, or better still, a line graph with points connected.
连续变异与非连续变异也是常见考点。身高和体重是连续变异（呈数值范围），而眼睛颜色、血型、卷舌能力等是连续变异吗？不——这些是非连续变异（清晰分类）。学生经常在应该用直方图（或更好的折线图）表示连续数据时，却错误地画了柱状图，导致失分。
9. Common Mistakes in Data Interpretation and Graphs | 数据解读与图表常见错误
Many Year 7 exams include a data table or graph to interpret. The number one error is not reading the axes labels and units. A graph with temperature in °C and time in minutes might ask 'how long did it take to reach 60°C?'—many students will read the scale incorrectly or quote the answer as '5' without the unit 'minutes'. Always include units with numerical answers unless the unit is already printed.
很多 Year 7 试卷包含需要解读的数据表格或图表。第一大错误就是不读坐标轴标签和单位。例如一张温度-时间图，纵轴是 °C，横轴是分钟，题目问'到达 60°C 用了多长时间？'，许多学生会读错刻度，或者回答'5'却漏写了单位'分钟'。除非题目已给出单位，否则数值答案必须带单位。
When calculating a mean, students sometimes omit to divide by the number of readings, or they include anomalous results without commenting. If you spot one reading far from the others, you should recalculate the mean excluding the anomaly and state your reason. This earns method marks. Never just ignore the anomalous result—you must identify it and explain why you excluded it.
计算平均值时，有的学生会忘记除以读数个数，或者在计算时把异常值也算进去，却又没有作出说明。如果你发现某个读数明显偏离其他数据，应该排除该异常值重新计算平均值，并写明理由。这个步骤能拿到方法分。绝不能不声不响地忽略异常值——你必须指出它是异常值并解释为什么排除它。
Line graphs often cause problems when students don' units, a sensible scale that uses more than half the grid, correctly plotted points (small '×' or dot), and a smooth line of best fit—or straight line segments if the question asks. Extrapolation questions ('predict the value when...') rely on you drawing the line correctly beyond the data.
画折线图时，学生常常因为比例尺不均匀、忘记标记坐标轴而丢分。评卷时考查的得分点包括：坐标轴上有物理量和单位；选取能利用一半以上网格纸的合理比例尺；正确描点（用小叉号或点）；并画出平滑的最佳拟合线——如果题目要求，也可以画直线分段连线。外推题（'当……时，预测值是多少？'）取决于你能否将图线正确延伸至数据范围之外。
10. Investigation Design and Experimental Skills | 实验设计与操作技能
Questions on planning an investigation look for: aim, variables (independent, dependent, control), hypothesis, equipment list, method, results table and conclusion. Students often lose marks by writing an aim that is too vague: instead of 'to find out about plants', write 'to investigate how light intensity affects the rate of photosynthesis in pondweed'. Similarly, the hypothesis should be a testable statement, e.g. 'As temperature increases, the time taken for sugar to dissolve decreases'.
设计实验的题目往往考查：目的、变量（自变量、因变量、控制变量）、假设、器材清单、方法、结果表和结论。学生常因目的写得太空泛而失分：不要写'为了了解植物'，而要写'为了研究光照强度如何影响水草光合作用速率'。同样，假设必须是一个可检验的陈述，例如'随着温度升高，糖溶解所需的时间缩短'。
In the method, use numbered steps and imperative language. A vital detail is specifying how you will measure the dependent variable and how you will change the independent variable—including instruments (stopwatch, ruler, thermometer, etc.) and their resolution. 'Measure the temperature' is not enough; write 'Measure the temperature using a digital thermometer to the nearest 0.1°C'. Mention repeats to improve reliability and how to deal with safety risks.
写方法时，要用编号步骤和祈使句语气。一个关键的细节是说明将如何测量因变量、如何改变自变量，包括所用仪器（秒表、尺子、温度计等）及其分辨率。'测量温度'这一描述不够充分；应写为'使用数字温度计测量温度，精确到 0.1°C'。此外，要提及重复实验以提高可靠性，并说明如何应对安全风险。
Failure to identify control variables is a top reason for losing marks. For example, in a dissolving investigation, control variables include the volume of water, the mass of solute (unless it is the independent variable), stirring speed, and the same apparatus. State at least two. Declaring 'do a fair test' alone offers no marks—name the specific controls.
遗漏控制变量是失分主要原因。例如在溶解实验中，控制变量包括水的体积、溶质的质量（除非它作为自变量）、搅拌速度和相同的实验装置。至少要写出两个控制变量。光说'做公平测试'没有分数——必须写出具体的控制变量。
11. States, Sub-Cellular Structures and Specialised Cells | 物态、亚细胞结构与特化细胞
Beyond the basic cell, Year 7 students are often introduced to specialised cells such as root hair cells, red blood cells, sperm cells and ciliated epithelial cells. Each adaptation must be linked to its function. For the root hair cell: a long extension increases surface area for absorption of water and minerals. Common error: saying the root hair provides anchorage—that is the function of the whole root, not the adaptation of the cell.
除了基本的细胞结构，Year 7 学生往往会学习特化细胞，如根毛细胞、红细胞、精子细胞和纤毛上皮细胞。每一种适应特征都必须与其功能联系起来。对于根毛细胞：其长长的突起增加了吸收水分和矿物质的表面积。常见错误：说根毛的作用是固定植物——那是整个根的功能，而非这个细胞的适应性特征。
For sperm cells, the flagellum (tail) enables movement to reach the egg; many mitochondria provide energy for swimming. For red blood cells, the biconcave shape increases surface area for oxygen exchange, and the lack of a nucleus maximises space for haemoglobin. These are fact-heavy, so make flashcards. Typical misstatement: 'red blood cells have no DNA'—true for mature human red blood cells, but they initially have a nucleus which is lost during maturation. In Year 7, it is enough to state they lack a nucleus.
精子细胞的鞭毛（尾巴）使其能够游动到达卵细胞；大量的线粒体为游动提供能量。红细胞双凹圆盘状的外形增大了气体交换的表面积，无细胞核的结构为血红蛋白腾出了最大空间。这些知识点记忆量大，建议制作闪卡。常见的错误说法：'红细胞没有 DNA'——成熟的哺乳动物红细胞确实没有细胞核和 DNA，但它们在成熟前是有核的，后来才退化。在 Year 7 阶段，只需说明红细胞无细胞核即可。
12. Exam Technique: Maximising Marks in Written Papers | 应试技巧：书面试卷得分最大化
Command words determine how you should answer. 'State' or 'give' means a short phrase or word; 'describe' means recount what you see or understand (no explanation needed); 'explain' means give a scientific reason, often using 'because'. The words 'suggest' or 'predict' test application to a new scenario. Every year, capable students lose marks by 'describing' when they were asked to 'explain', or vice versa.
指令词决定了你的答题方式。'陈述'或'写出'意味着用简短的词语或短语作答；'描述'意味着说出你所见到或理解的内容（无需解释原因）；'解释'则要求给出科学理由，通常要用到'因为'这个词。'建议'或'预测'则考查你将知识运用到新情境中的能力。每年都有优秀学生因为要求'解释'却去'描述'，或者要求'描述'却去'解释'而失分。
For multi-step calculation questions, always write the formula, substitute numbers, then give the answer with units. Even if the final answer is wrong, you can pick up method marks. Checking answers: does your number make sense? If you calculate a speed of 800 m/s for a bicycle, something is wrong—perhaps you used cm instead of m.
对于多步计算题，一定要写出公式、代入数字，再写出带单位的答案。即使最终结果错了，也能拿到过程分。检查答案：你的数字符合常理吗？如果你算出一辆自行车的速度是 800 m/s，那肯定哪里出错了——可能是混淆了厘米和米。
Lastly, time management is crucial. Many Year 7 papers have a mixture of short 1-mark questions and longer 3–4 mark questions. Do not spend 10 minutes on a 1-mark diagram label if you haven't answered the longer questions at the back. Leave space and move on; return if time allows. Always read through the paper once before writing to gauge the distribution of marks.
最后，时间管理至关重要。很多 Year 7 试卷混合了 1 分的小题和 3–4 分的大题。不要为了一道 1 分的标注图标签题而花上 10 分钟，却把后面的大题晾着不管。留出空位，先做后面的，有时间再回来补。写作前先把整份试卷浏览一遍，估清分值的分布。
Published by TutorHao | Science Revision Series | aleveler.com
更多咨询请联系16621398022（同微信）
或截图后用「扫一扫 → 相册」选择本图