—Excuse me,is this the right way to the bookstore?—Sorry,I’m not sure.But it________be.
It’s impolite to _____ your parents. You should talk to them politely.
_____ prepare for the coming exam, Dave stays up late every night.
We can’t put off _____ a plan. We should do it right now.
--- The twin boys look sad. Let’s _____ . --- OK!
I saw a dog _____ on the side of the road when I passed by.