Many (自愿者)often come to the countryside to help the poor.
五月份有31天.
有人担心将来机器人会取代人类.
Some people worry that robots will take the place of humans the .
我们应该在扔掉废物前进行分类.
We should divide the waste into different groups before it .
他们一大早就动身去伦敦旅行了.
They for London on a holiday early in the morning.
Danniel did the exercises too (粗心地), and it made his teacher angry.