April is ___________ month of a year.

______ and short of breath, Andy and Ruby were the first to reach the top of Mount Tai.

It is well known to us all that a lot of rivers _______by factories

I didn’t hear you in just now.—That’s good. We tried ________________ you up.

When will you come to see me, Mum—I will go to see you when you____ the class.