—Must we finish the project in a month?—No, you _______. 

I told Sally how to get here, but perhaps I ______for her.

The doctor said he _______ an operation yet.

—Do you know whose dictionary it is?—It ________ be Ann’s. Look! Her name is on the first page.

—It's no easy task to catch a ticket on a website that receives 1 billion clicks daily.—I can't agree with you more. There ________ be errors for every single step.