______ it is to learn English on the internet! 
#66256
A
What a fun
B
What fun
C
How a fun
D
How fun
推荐题目
     , and the problem will be worked out.
#66110
A
If you have a bit more effort
B
Having a little effort
C
A bit more effort
D
There being a little effort
_____wild animals when you go up the hill.  
#66144
A
Look out for
B
Take care
C
Take care of
D
Be careful
 ________ at the door before you enter my room, please.
#66075
A
Knock
B
Knocking
C
Knocked
D
To knock
 _______ your mind and you will find the way.
#66254
A
Using
B
Use
C
If you use
D
To use