In the past twelve months the research members ______ the effectiveness of many materials in a home building.
#102889
A
had studied
B
would study
C
studied
D
have studied
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Every possible means  _____  .
#103742
A
has tried
B
has been tried
C
was tried
D
were tried
Alice _____ in a book that the city she lives in was _____ one hundred years ago.
#101516
A
found, found
B
founded, founded
C
founded, found
D
found, founded