1.When the students came into the classroom,the teacher ( ) on the blackboard.
问题描述：
1.When the students came into the classroom,the teacher ( ) on the blackboard.
A:is writing
B:was writing
C:wrote
2.I have ( )to tell you
A:important something
B:something important
C:something importantly
3.The joke kept us ( )
A:laughing
B:to laugh
C:laugh at
答
1.B
2.B
3.A