With the help of high technology, many new substances（物质）______in the past years.
#102927
A
discovered
B
have discovered
C
had been discovered
D
have been discovered
推荐题目
Months ago we sailed ten thousand miles across this open sea，which the Pacific，and we met no storm．
#102005
A
was called
B
is called
C
had been called
D
has been called
Liu Ming is said abroad for one year before he came to teach in our school．
#103093
A
to have studied
B
to study
C
to be studying
D
to have been studying
--Why does the lake smell terrible? -- Because a large amount of water_______.
#99621
A
have polluted
B
is being polluted
C
has been polluted
D
have been polluted
---Shall I go to the party tomorrow? ---I would rather _____.
#103056
A
come
B
should come
C
would come
D
came
Thank you for your visit to CCTV.COM. This site ____ and will be back online in the not—too—distant future.
#104087
A
had updated
B
will be updated
C
updated
D
is being updated