单选题 They keep tellirig us.that it is vital that we ______ there on time.
A. are B. be C. must be D. would be

【正确答案】 B
【答案解析】[解析] 本题考查要点：虚拟语气在特殊句型中的用法。在it is vital/important/necessary/desirable that……句型中，that引导的主语从句中谓语动词用动词原形或should+动词原形的虚拟语气形式。