Since nobody gave him any help, he    have done the research on his own.

—My daughter mastered Japanese in less than two years.—Did she? She         have a gift for language.

 I’d rather you did some housework when you are free ,but you       .

You ____be tired—you have worked only for ten minutes．

---- Is it good to look up every new word when I come across it in reading?---- No. You ________,  because you are likely to guess the meaning from the context.