Thank you for your help, Linda. You made ________ possible for us to finish the work in time.
-- Did you read a book about customs last week?-- Yes, I found ______ very useful to know the customs of foreign countries.
--You used to be quiet, ____you?--Yes, and I used to be very shy.
-- How do you study a test? -- I study listening to tapes.
--What’s the matter? --They said I shouldn’t be allowed here. They don’t allow in the waiting room.
--Listen! Tom is singing in the next room.--It _______ be Tom. He has gone to Shanghai.