Where are your children—I had no idea. But when I left home this morning, I saw them _______ a football in the yard.

He is only too ready to help others,seldom,______, refusing when they turn to him for help.[ ]

Little Tom went to the stadium in a hurry, only______ the game had been put off.

Do you think it’s a good idea to make friends with your students?— ________, I do I think it’s a great idea[ ]

下列各句中，表达得体的一句是