________ repeatedly, the problem still appeared in the beginners’ homework.
#100762
A
Explaining
B
Having explained
C
Having been explained
D
To be explained
推荐题目
You _____ television. Why not do something more active?
#101343
A
always watch
B
are always watching
C
have always watching
D
have always been watching
—What’s that noise,John?—Sorry,Linda.I forgot to tell you.The school library________.
#99403
A
is rebuilt
B
is being rebuilt
C
was rebuilt
D
has been rebuilt
Large quantities of information, as well as some timely help ________ since the organization was built.
#100487
A
has offered
B
had been offered
C
have been offered
D
is offered