Some of the students have already learned enough English to ____ a conversation with a native English speaker.   
#83315
A
hold on
B
keep on
C
go on
D
carry on
推荐题目
Usually children are allowed to ______ when they are six years old.
#84133
A
attend school
B
attend the school
C
join school
D
join the school
 We must ___ on our study..
#80547
A
concentrate
B
concentrate at
C
concentrate on
D
concentrate with