Scientists say it will be five or six years _____ it is possible to test this medicine on human patients.
#68451
A
before
B
that
C
since
D
when
推荐题目
“My boy, do remember to leave things _____ you can find them again.
#67732
A
where
B
when
C
then
D
there
It is not always easy for the public to see _______ benefit a new invention can be of to human life.
#68436
A
whose
B
what
C
which
D
that
Please arrange an interview with the manager tomorrow , or it is convenient to him .
#68104
A
whenever
B
however
C
whichever
D
wherever
Electronic devices such as iPods and headphones can do great harm to our hearing if _______ improperly.
#67875
A
being used
B
used
C
to be used
D
having been used