Reading: The Plastic Bag Numbers That Rebounded
You are reading a 400-word passage in the reading section. The passage is about Hikari Town's plastic bag campaign. In 2019, all 12 supermarkets began charging 5 yen per plastic bag. Before the charge, the town used about 3,000 bags per day. Six months later, the number was about 1,200. In 2021, the town allowed takeout containers at events, and the number rose to about 1,800. The passage ends: 'The town learned that a charge alone was not enough; it had to keep reminding people why they were doing this.'
One question asks for the main idea. You are hesitating between two choices: A says the charge reduced bags by 60% in six months. B says the town needs to combine the charge with other measures because the effect can fade. A contains a correct number, so it looks safe. B feels like an opinion. You have one minute left.
1. Which choice is the main idea, A or B? Explain why the other true-sounding choice is not the main idea.
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B is the main idea. The passage's final sentence states the lesson directly: a charge alone was not enough, and the town had to keep reminding people. B restates that lesson.
A is a true detail: 3,000 to 1,200 is a 60% drop in six months. But A stops at the six-month result. It does not cover the 2021 rebound to 1,800 or the town's conclusion. In main-idea questions, a choice that is accurate but covers only one part of the passage is a trap. D is also true (1,800 is less than 3,000), but it is a comparison, not the lesson. C overstates the passage: takeout containers contributed to the rise, but the passage does not say they were the main cause.
2. Use the numbers to explain what 'the effect can fade' means in this passage.
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The effect is the drop from 3,000 to 1,200 bags per day, a reduction of 1,800 bags or 60%. 'Fade' means the reduction did not stay at 1,200: it rose to 1,800 in 2021.
That is still 1,200 fewer than the original 3,000, so the campaign did not disappear completely. But it lost 600 bags' worth of improvement. The passage uses this rebound to argue that one charge at the start is not a permanent fix.
3. If a new sentence were added - 'In 2022, a reusable-bag campaign began, and the number fell to 900' - would that weaken or strengthen B? Explain.
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It would strengthen B. B says the town needs to combine the charge with other measures. The 2022 reusable-bag campaign is another measure, and the drop from 1,800 to 900 shows that adding it helped.
It does not weaken the main idea; it gives a second example of 'charge plus something else.' A detail-only answer like A could not easily use the 2022 number, because A is fixed on the first six months.