Do you have any ideas ________ is actually going on in the classroom?

Jerry ________ with a stranger when I met him on the way to work yesterday.

Peter said that he would come over to have dinner with you tonight.—But I think he. I have been alone for an hour.

He was _____ to tell the truth even to his closest friend.

In such dry weather, the flowers will have to be watered if they ________.