【C2】A．WhileB．AsC．SinceD．Unless

【B3】A．IfB．AsC．ThoughD．Unless

【C2】A．BeforeB．OverC．SinceD．From

【C17】A．WhileB．AlthoughC．SinceD．So

【C18】A．WhileB．OnceC．SinceD．Though

【C2】A．IfB．UntilC．DespiteD．Unless

【C2】A．WhileB．As soon asC．MeantimeD．Before