兒童英語(yǔ)故事短文：熱脹冷縮

Teacher：We all know that beat causes an object to expand a cold cauese it to contract.Now,can anyone give me a good example?

John：Well ,in the summer the days are long,and in the winter the days are short.

老師：我們都知道熱脹冷縮的道理?，F(xiàn)在，誰(shuí)給我舉個(gè)例子?

約翰：嗯，在夏天天都長(zhǎng)，在冬天天都短。