问题:
Water the tree ________ you can.
A.so often as
B.as often as
C.more often than
D.as possible as
Water the tree ________ you can.
A.so often as
B.as often as
C.more often than
D.as possible as
A.so often as
B.as often as
C.more often than
D.as possible as
参考答案: