过去我的祖父曾当过童工 my grandpa used to be a child laborer in the past [used to do sth 过去曾怎么样,但现在不这样了]我们这个地区虽然不缺水，但应该节约 our area is not lack of water, but we should save it [be lack of sth 缺少什么] 你知道印度的人口比美国的还多吗 do you konw that the population of India is larger than that of America [larger than sth 比什么更哒]老师告诉我们噪音对我们耳朵的伤害很大 the teacher told us that noise is very harmful to our ears 你务必回来 Make sure that you come back [make sure 确保什么]
