No one has yet succeeded in explaining the ___ of how life began.
#6736
A
cause
B
problem
C
reason
D
puzzle
推荐题目
Our new English teacher made a strong ______ on all of us with his humorous speech.
#5889
A
description
B
contribution
C
impression
D
expression
I broke my relationship with John because he always found_______ with whatever I did．
#6005
A
error
B
mistake
C
fault
D
failure
It said the country's confirmed H7N9 cases were isolated and there has been no______ of human-to-human transmission.
#5258
A
mark
B
symbol
C
sign
D
signal
In considering people for jobs, we give ____ to those with some experience.
#5445
A
decision
B
attempt
C
preference
D
reputation