I don’t know how ________ commas. 
#69179
A
use
B
using
C
used
D
to use
推荐题目
It’s a beautiful toy, ____?
#71197
A
is it
B
isn’t it
C
has it
D
doesn’t
— When I was young, I liked playing with toy animals. — ______. 
#70950
A
So I was
B
So was I
C
So did I
D
So I did
—______are you staying there?—Just for two days. 
#70729
A
How long
B
When
C
How often
D
How many
Zhu Zhiwen’s never been to Hongkong, _______?
#71065
A
is he
B
isn't he
C
has he
D
hasn't he