The boy isn’t old enough ________ with the difficult problem by himself. 
#50365
A
deal
B
deals
C
dealing
D
to deal
推荐题目
I think the room is too small for us ________ .
#48823
A
to live
B
living in
C
to live in
D
live in
Mary used to _____short hair.
#49101
A
be
B
have
C
had
D
has
The boy was seen            on the sports ground.
#50866
A
to play
B
play
C
played
D
to playing
We know that she enjoys ______ books very much.
#50640
A
read
B
reads
C
reading
D
to read