With the help of high technology, more and more new substances ______ in the past years.
#104082
A
discovered
B
have discovered
C
had been discovered
D
have been discovered
推荐题目
----- How about the book you are reading now? ----- Excellent indeed. You can find many problems we have come across _____ in it.
#103288
A
covered
B
covering
C
are referred
D
referred
By the time I got to the office, the meeting ______.
#100849
A
had begun
B
began
C
was beginning
D
would begin
A vast area north of the Yangtze River ______by the first heavy SNOW of the new year，causing difficulties to the post-festival road transport.
#102259
A
were affected
B
was affected
C
had affected
D
has affected
----The train will arrive at the station in half an hour. Who ______for us? ----I am sure Dad will be standing there when we get off the train.
#101310
A
will be waiting
B
was to wait
C
wait
D
was about to wait
—Have you got any trouble finding your way in Shanghai? — Yes，I tried to fid the way to the airport but ______.
#103072
A
has been lost
B
got lost
C
lost
D
get lost.