As there is less and less coal and oil, scientists are exploring new ways of making use of ____ energy, such as sunlight, wind and water for power and fuel.
#18985
A
original
B
alternative
C
convenient
D
staple
推荐题目
Wait till you are more ________. It’s better to be sure than sorry.
#20721
A
alternative
B
satisfied
C
optimistic
D
certain
—Shall we go to see him right now?—I’m afraid not. This weekend may be a ____time
#19730
A
good
B
better
C
best
D
well
The______ look on his face shows that he’s greatly ______.
#59552
A
terrified; terrifying
B
terrified; terrified
C
terrifying; terrifying
D
terrifying; terrified
----Be careful not to drop the Ming Dynasty vase. ----Yes, we can’t be _____.
#20686
A
too careful
B
very careful
C
too careless
D
careless enough
Taking medicine only gives you _______ relief from pain, so I suggest you have an operation.
#18908
A
flexible
B
optional
C
temporary
D
beneficial