It was John ______ clearn the window.
A. Who
B. whom
C. what
D. which
Was it by train _____ you traveled last summer?
A. which
B. what
C. and
D. that
It was soon after the economic crisis ______ sales of e-business started to grow. (2013,6.A)
A. Why
B. how
C. where
D. that
It was not until 3:00p.m. _______ the secretary found the missing report. (2013, 12 B)
A. Where
B. that
C. as
D. while
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