Question

1. I'm afraid I can't finish the work ____________to help me. A. unless you will come B. unless you

Answer 1

B
unless是从属连词，引导条件状语从句，含有否定意义，相当于if条件状语从句的否定形式。所以unless = if not。注意：unless引导的条件状语从句和if条件状语从句，与其它时间状语从句一样，用一般现在时代替将来时。
1. Unless you take more care, you’ll have an accident.
(如果不多加小心的话，你会出事故的。)
2. My baby sister never cries unless she is hungry.
(我那刚出生的妹妹除非饿了，否则她是从来不哭的。)
3. Unless bad weather stops me, I jog every day.
(除非坏天气阻拦我，否则每天我都慢跑的。)

Answer 2

B
这种情况是不用将来时态的。再说，将来时态句意也说不通啊：我（现在）完不成工作除非你将来帮我=你将来帮助我，我现在就能完成工作。

Answer 3

B unless you come 让步状从，不用将来时，unless=if not

Answer 4

b

Answer 5

until you come