—Sorry we’re late.We ______ the wrong turning.—That’s all right.Come in, please.
---- It is generally believed that teaching is __________it is a science.
----Three students came late to school this morning, Tom and Jack_______.
----Drinking is harmful_______our health.
----Must I finish the jod at seven o’clock?----No, you___________
---- The reason why he has been such a success is ________he had lost his money.