Have you heard of Earth Day ?—-Yes . The first Earth Day ______ in 1970 to educate us to protect our planet .
It’s said that this kind of milk ________ well this year. It will be sold out soon.
How long have you been a League member?—_____two years ago.[ ]
Must I finish the work today? — No, you _____.
Why did you leave without a word of warning to John? ——But what_____________otherwise? He never listens to me.