The research is so designed that once _____ nothing can be done to change it.
#95029
A
begins
B
having begun
C
beginning
D
begun
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It was a matter of________ would take the position.
#93712
A
who
B
whoever
C
whom
D
whomever
 He knew the problem was serious and promised to look into it _____ he reached office.
#94818
A
at that moment
B
for that moment
C
immediately
D
soon
I kept looking at the man, wondering _______.
#93460
A
whether I have seen him before
B
whether I had seen him before
C
that I had seen him before
D
when I saw him before