Hewas______towithdrawfromrunningforthepresidency.
C
句意：他被说服退出竞选总统。 convince 使相信;信服;说服。
Thenewdiscovery_______beofgreatservicetomankind.
Theprofessoraskedaquestion,andDavid________agoodanswer.
It rained hard yesterday, ______ prevented me from going to the park.
The central theatre has a seating ________ of more than 3, 000 people.