-What's up? You look worried.Well,I_____on the problem for 5 hours but I haven't got a single clue.
#100541
A
have worked
B
worked
C
will work
D
have been working
推荐题目
The five rings on the Olympic flag ______ the five continents that are joined together in the Olympic Games.
#99677
A
belong to
B
stand for
C
take apart
D
pack up
The dish _____ nice, but the milk _____ sour.
#103726
A
is smelt, is smelt
B
is smelt, smells
C
smells, is smelt
D
smells, smells
—What’s the noise? —Oh, I forget to tell you. The new machine .
#99908
A
has been tested
B
is tested
C
will be tested
D
is being tested
____is known to all, good friends _________ happiness and value to life.
#99280
A
It; add
B
As; add
C
It; add up
D
As; add to
When their first child was born, they _________ for three years.
#103499
A
had married
B
had been married
C
got married
D
had got married