You can hardly imagine the once clear canal _____ so seriously polluted that no fish can live in it. [ ]

Whose guitar is this Susan plays the guitar. It must _______.

It there anyone in your class ______family is in the country?

The machine I have looked after for twenty years is still working well.

I’m sorry I ______ my homework at home.– That’s all right. Remember ______ it to schooltomorrow.