The graph shows how temperature of the surroundings affects the growth rate of some plants.
Andy and Bernard made the following statements.
Statement
Andy
The growth rate of the plants decreases as temperature increases from 25°C to 45°C.
Bernard
As temperature of the surroundings increases from 40°C to 45°C, the growth rate of the plants remains the same.
Who is/are correct?
AAndy only
BBernard only
CBoth Andy and Bernard
DNeither Andy nor Bernard
看答案和讲解
正确答案：B. Bernard only
考点读懂折线图 · Experimental skills: reading a line graph
思路：从 25°C 到 40°C 生长速率下降，但 40°C 到 45°C 曲线是平的，速率不变。所以 Andy 说“25°C 到 45°C 一直下降”不对，Bernard 对。 Think: The growth rate falls from 25°C to 40°C but stays the same from 40°C to 45°C. So Andy is wrong and Bernard is correct. 小提醒：看清每一段的趋势，平线表示不变。 Tip: A flat line on a graph means no change.
第 2 题力南洋小学 2026 Prelim 第 18 题
Harvey measured the lengths of two springs, S and T, when different loads were hung on them as shown below. Spring T is stiffer than spring S.
Which graph correctly shows his results?
A
B
C
D
看答案和讲解
正确答案：B.
考点弹力：弹簧长度与负载 · Elastic spring force: length of spring vs load
思路：弹簧不挂东西时也有原来的长度，所以两条线都不是从 0 开始，而是从同一个原长开始。T 更硬，同样的负载伸长得少，所以 T 的线比 S 平缓。符合的是 (2)。 Think: With no load, each spring already has a length, so the lines start above 0. T is stiffer, so it stretches less and its line is less steep than S. This matches graph 2. 小提醒：纵轴是“长度”，不是“伸长量”。 Tip: The y-axis shows length, not extension.
第 3 题力南洋小学 2026 Prelim 第 19 题
Two metal balls, K and L, are shown below.
The balls are dropped from the same height into a container of water as shown below.
Which graph best represents the amount of gravitational force acting on the balls, K and L, at positions D and E?
A
B
C
D
看答案和讲解
正确答案：A.
考点重力：与质量有关，与位置无关 · Gravitational force: depends on mass, not position
思路：物体受到的重力只和它的质量有关。K 是 50 g，比 L（25 g）重，所以 K 受到的重力更大。从 D 沉到 E，质量没变，重力也不变。所以两个位置的柱子一样高，而且 K 高于 L，选 (1)。 Think: Gravitational force depends on mass. K (50 g) is heavier than L (25 g), so K has more gravitational force. Their masses do not change from D to E, so the forces stay the same. 小提醒：在水里位置变了，重力并不变。 Tip: Moving deeper in water does not change gravity.
第 4 题光与影子南洋小学 2026 Prelim 第 24 题
The diagram below shows the positions of the sun at different times of the day.
Which graph shows the length of the tree’s shadow correctly?
A
B
C
D
看答案和讲解
正确答案：D.
考点影子：太阳高度与影子长度 · Shadows: height of the sun and shadow length
思路：太阳越低，影子越长；太阳越高，影子越短。早上 8 点太阳最低，影子最长；10 点短一些；12 点太阳最高，影子最短。影子一直变短，所以选 (4)。 Think: The lower the sun, the longer the shadow. At 8 am the sun is lowest, so the shadow is longest. It gets shorter at 10 am and shortest at 12 noon. Graph 4 shows this. 小提醒：中午太阳在头顶，影子最短。 Tip: At noon the sun is highest and the shadow is shortest.
第 5 题生物间的相互作用道南学校 2026 Prelim 第 11 题
The diagram below shows a food web.
Which of the following will most likely take place within a week when a new disease kills organism E in the community above?
AB will feed on more A
BPopulation of A will increase.
CC will have more A to feed on.
DPopulations of all the other organisms will decrease.
看答案和讲解
正确答案：A. B will feed on more A
考点食物网中某生物消失的影响 · Food webs: effect of removing one organism
思路：箭头指向“吃的一方”。B 吃 E 和 A。E 病死后，B 少了一种食物，只能吃更多 A。A 被吃得更多，数量不会增加；C 吃 A 和 B，不一定有更多 A 吃。 Think: Arrows point to the eater. B eats both E and A. When E dies, B has to feed on more A. So A will not increase, and C will not get more A. 小提醒：一种食物没了，捕食者会多吃另一种食物。 Tip: When one food is gone, the consumer eats more of its other food.
第 6 题电道南学校 2026 Prelim 第 24 题
A new bulb is connected to the circuit as shown below.
What will happen to the brightness of bulbs X and Y?
AX: increases; Y: increases
BX: increases; Y: decreases
CX: remains the same; Y: does not light up
DX: remains the same; Y: remains the same
看答案和讲解
正确答案：D. X: remains the same; Y: remains the same
考点并联电路中灯泡的亮度 · Electricity: brightness of bulbs in parallel branches
思路：X 所在的支路和 Y 所在的支路都直接接在电池两端，新加的灯泡接在另一条支路上，不会改变 X 和 Y 支路两端的电压，所以 X、Y 亮度都不变。 Think: The branches with bulb X and bulb Y are each connected straight across the batteries. The new bulb is added in another branch, so the brightness of X and Y stays the same. 小提醒：并联支路互不影响。 Tip: Parallel branches do not affect each other.
第 7 题植物与动物的繁殖圣尼各拉女校 2025 Prelim 第 1 题
The characteristics of four flowers W, X, Y and Z are shown in the following chart.
Pollinator P flies in the day and is attracted to brightly coloured flowers. Which flower W, X, Y or Z is most likely pollinated by pollinator P?
AW
BX
CY
DZ
看答案和讲解
正确答案：C. Y
考点植物繁殖：传粉者与花的特征 · Plant reproduction: pollinators and flower features
思路：P 在白天活动，所以花不是“只在晚上开”，第一格选 no；P 喜欢颜色鲜艳的花，“Is brightly coloured?” 选 yes，得到 Y。 Think: P flies in the day, so the flower does not bloom only at night (no). P likes bright colours, so "Is brightly coloured?" is yes. That gives Y. 小提醒：沿着流程图一格一格走，每一步都对照题目给的信息。 Tip: Follow the chart one box at a time and check each step with the clues.
第 8 题生物间的相互作用圣尼各拉女校 2025 Prelim 第 11 题
The graph below shows how the population of two different organisms, E and F, are affected by the rise in Earth’s temperature.
Based on the graph above, which of these statements is true?
ABoth organisms E and F can survive at 40 °C.
BBoth organisms E and F cannot survive at 0 °C.
COrganism E prefers to live in a warmer environment.
DThe population of organism F increases with increasing temperature.
看答案和讲解
正确答案：C. Organism E prefers to live in a warmer environment.
考点环境：温度对生物数量的影响（读图） · Environment: effect of temperature on populations (reading a graph)
思路：E 的数量随温度升高一直增加，说明 E 喜欢较暖的环境；F 的数量随温度升高而减少，(4) 错。图只画到 36 °C，看不出 40 °C 和 0 °C 时的情况，(1)(2) 都不能下结论。 Think: E’s population keeps rising as it gets warmer, so E prefers a warmer place. F’s population falls, so (4) is wrong. The graph does not show what happens at 40 °C or at 0 °C, so (1) and (2) cannot be concluded. 小提醒：只根据图上有的信息作答。 Tip: Only use what the graph actually shows.
第 9 题材料圣尼各拉女校 2025 Prelim 第 13 题
Study the flow chart below.
Based on the flow chart above, which of the following is correct?
AQuestion A: Is it waterproof? Question B: Does it float on water? S: styrofoam
BQuestion A: Does it allow light to pass through? Question B: Does it break easily? S: ceramic
CQuestion A: Does it float on water? Question B: Does it allow light to pass through? S: metal
DQuestion A: Does it allow light to pass through? Question B: Is it waterproof? S: cardboard
看答案和讲解
正确答案：D. Question A: Does it allow light to pass through? Question B: Is it waterproof? S: cardboard
考点材料：用流程图给材料分类 · Materials: classifying materials with a flow chart
思路：玻璃能透光，所以 Question A 是“Does it allow light to pass through?”。橡胶防水且柔韧，所以 Question B 是“Is it waterproof?”；不防水的 S 可以是纸板。答案 (4)。 Think: Glass lets light through, so Question A asks about light. Rubber is waterproof and flexible, so Question B asks "Is it waterproof?". S is not waterproof: cardboard. 小提醒：用已知的答案（glass、rubber）反推问题。 Tip: Use the known answers (glass, rubber) to work out the questions.
第 10 题电南华小学 2025 Prelim 第 19 题
When a bulb was blown in the circuit, one other bulb did not light up.
Which bulb was blown?
AW
BX
CY
DZ
看答案和讲解
正确答案：A. W
考点电路：串联与并联中坏掉一个灯泡的影响 · Circuits: effect of a blown bulb in series and parallel
思路：W 和顶上的灯泡串联在一条支路上，这条支路又和中间斜线上的灯泡并联。W 坏了，只有和它串联的顶上灯泡不亮（只有 1 个）。X 坏了，其他灯泡都还亮；Y 坏了，W、顶上灯泡和中间灯泡都不亮（3 个）；Z 坏了，全部不亮。 Think: W is in series with the top bulb only. If W blows, just that one bulb goes out. If Y blows, three bulbs go out; if Z blows, all go out; if X blows, the others stay lit. 小提醒：坏掉的灯泡会断开与它串联的灯泡。 Tip: A blown bulb switches off the bulbs in series with it.
