Question

--- I wonder how much you charge for your service.
--- The first two are free ______ the third costs $30.

A．while

B．until

C．when

D．before

Answer 1

A

考查連詞。While 意為然而，表對比， until直到  when當……時候  before在之前
句意為，---我想知道你的服務要收多少錢？
-----前面兩個免費，然而第三個要三十美元。