I ___ go to see the doctor last week because I was very ill.

I ___ go now because I am already late for my class.

___ you come over for dinner on Friday night? I really want to hang out with you, so I hope you can come.

She ___ be crazy! She wants to backpack through the Andes by herself.

If you tell your boss off, you ___ surely be fired.

You ___ worry all the time. Don't be so negative. You should be more optimistic about life.