题目

题型：不详难度：来源：

_____________ all the seats were full, he had no choice but to stand up.

A．For

B．As

C．Though

D．Unless

答案

B

解析

考查连词的用法。For 因为，只能放在句中不能放在句首，As 因为，Though 虽然，Unless 除非，句意：因为所有的座位都满了，他别无选择除了站着。所以选B。