The price of food, clothes, houses __________ so quickly these years. —Yes. I think so.

Beijing’s first unmanned subway trains, which can run ______ without the control of any drivers, are expected to be put into operation next year.

Do you think I should accept his invitation, Jim—________If I were you, I certainly would.

It’s certainly hard work.But, ________, a man who wishes to have a career has to make a great many sacrifices.[ ]

一Please give Maria this letter.一OK, I’ll .