With the help of high technology, more and more new substances ___in the past few years.
#101737
A
discovered
B
have discovered
C
had been discovered
D
have been discovered
推荐题目
You can’t imagine what great trouble the doctor had ______ the patient.
#103047
A
treats
B
treating
C
to treat
D
treated
一Did he notice you enter the classroom?一I don’t think so．He _______ to the radio with his eyes shut·
#101731
A
1istened
B
was listening
C
has listened
D
had listened
Don’t disturb me. I_______ letters all morning and have written ten so far.
#100860
A
have written
B
am writing
C
was writing
D
have been writing
The film Let the Bullets Fly _____ a great success and brought in a large profit to the cinema.
#102861
A
was enjoyed
B
enjoyed
C
is enjoyed
D
enjoys
Please make sure that no details _____ before you deliver a speech.
#100382
A
would be overlooked
B
will overlook
C
are overlooked
D
are overlooking