________the working efficiency，the boss allows the employees to have a coffee break.
#88719
A
Improving
B
To improve
C
Having improved
D
Improved
推荐题目
The news shocked the public, to great concern about students’safey at school.
#96365
A
having led
B
led
C
leading
D
to lead
The operation I had just two months ago and now I have fully recovered．
#92537
A
taken place
B
took place
C
to take place
D
taking place
_________the answer, the boy, who asked the question, still stood with his hand ______.
#90345
A
Giving, raised
B
Giving; rising
C
Given; risen
D
Given; raised
The poor little boy ______ by his heartless parents was seen begging in the street.
#89727
A
abandoning
B
to be abandoned
C
having abandoned
D
abandoned