In 1962, engineer Sten Gustaf Thulin invented a packaging material which could be divided into individual shopping bags at checkouts. Today, in New Zealand, we use a billion of these single-use plastic shopping bags annually. It's only a few local councils that accept them in recycling collections, and just a handful of supermarkets that offer the same service. In North America, it's an approximate 100 billion bags a year, a far higher number, but unsurprising, given the greater population. But where do they end up? A 2014 study estimated that over five trillion pieces of plastic are now floating in the ocean. Shopping bags account for much of that waste. Even when plastic bags are sent to council landfills, the massive sites where rubbish is dumped, this still creates problems. The length of time it takes for bags to break down and biodegrade depends on how much sunlight they're exposed to. If exposed the whole time, it might take ten years. At the bottom of landfills, it might take a century. Researchers also suspect that plastic bags don't actually break down completely, but just become microscopic pieces which then find their way into rivers and streams, and into soil. This may have a worse ecological impact than we yet understand.
📝 题目要求
找出文本中的逻辑关系词,并写出对应的逻辑类型
找出文本中的逻辑关系词；并写出所对应的逻辑类型：
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✅ 参考答案与解析
and：并列 2. but：转折 if：条件 also：并列 and：并列关系。说明在新西兰接受和提供一次性塑料购物袋回收服务的情况。 2. but：转折关系。说明鉴于人口更多，这个高数量并不令人惊讶 if：条件关系。说明 “如果塑料袋一直暴露在阳光下” 这个条件 also：并列关系。进一步说明研究人员怀疑塑料袋实际上不会完全分解