1. One day Chuck is on a flight across the Pacific Ocean ­_______ suddenly his plane crashes.

A.    since                                          B.    when

C.    while                                         D.    though

2. --- He works hard at English.

--- _______ and _______Joe.

       A.    So he is; so does                          B.    So is he; so do

       C.    So he does; so is                          D.    So he does; so does

3. --- We missed the first part of the play. What a pity£¡

--- We  ­_______ earlier.

       A.    would have started                B.    should have start

       C.    should have started               D.    must have started