After a long walk, they were _______tired that they could not move even one step further.

Keys should never be hidden around the house since thieves _____ know where to look.

 There was such a long queue for coffee at the interval that we _____gave up.

-- Do you think it's a good idea to make friends with your students?--  _____  , I do. I think it's a great idea.

I don’t mind picking up your things from the store. ______, the walk will do me good.