Scientist are not sure about the ___________ of water on the Mars.
#6679
A
occupation
B
existence
C
demand
D
treasure
推荐题目
Premier Wen Jiabao has many important ______ of state to deal with.
#6506
A
affairs
B
matter
C
business
D
thing
The police are offering a big ___________ for information about the robbery.
#5168
A
award
B
prize
C
reward
D
money
These natural disasters have warned us that everyone should start to protect the_________ immediately.
#6062
A
amusement
B
development
C
environment
D
government
—Where does your sister work, Jack? —She works in a ___________.
#6820
A
shopofcloth
B
cloth’sshop
C
shopwithclothes
D
clothesshop
Life is full of _______.School is thought as the most _______ obstacle(障碍) in the lives of youth today.
#5478
A
challenge; challenging
B
challenges; challenged
C
challenges; challenging
D
challenging; challenges