________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
Bats are surprisingly long-lived creatures, some ___ a life span of around 20 years.
#94661
A
have
B
had
C
having
D
to have
Attempting to get home before dark, ___________
#98460
A
Tom’s bike broke down on the way
B
it happened that Tom’s bike hit a car
C
a car knocked Tom off his bike
D
Tom knocked into a tree
Mother told me ________a noise in the hall.
#96422
A
don’t make
B
make not to
C
not to make
D
to make not
The salesman scolded the girl caught ____ and let her off．
#88678
A
to have stolen
B
stealing
C
to steal
D
to be stealing