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。
Thebookfairhasreceivedapositive________fromreaders.
Hewouldhavegivenyoumorehelp,ifhe________sobusy.
CharlesSmith,______wasmyformerteacher,retiredlastyear.
Thecentraltheatrehasaseating________ofmorethan3,000people.
Studentsshould_____theirowninterestsaswellasdotheirschoolwork.
