The new discovery _______ be of great service to mankind.
A、isboundtoA
beboundto：注定要，一定会。本题中主语是Thenewdiscovery，所以谓语动词要用is。句意：这项新发现对于人类必定大有用处。
He would have given you more help, if he ________ so busy.
He blamed his poor performance_____jet lag.
Charles Smith, ______ was my former teacher, retired last year.
Ittookmeamonthtogetrid_______thecough.
IsitShakespeareTheatre_______youaregoingtowatchtheplayTheMerchantofVenice?
