The new discovery _______ be of great service to mankind.
A
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。
Theyareeager_______abroad.
Studentsshould_____theirowninterestsaswellasdotheirschoolwork.
Idon’tneedanyhelpatthemoment,butI_____youroffer.
Theprofessoraskedaquestion,andDavid________agoodanswer.
Heblamedhispoorperformance_____jetlag.