A new technique __________ , the yields as a whole increased by 20 pe-考呗网题库移动版

单选题 A new technique __________ , the yields as a whole increased by 20 percent.

A．working out
B．having worked out
C．having been worked out
D．to have been worked out

参考答案C

解析:

单选题 The United States Constitution provides for a count of the population __________ a census, every ten years.

A．called
B．which called
C．that it is called
D．as called

单选题 Just as a force is required to change the speed of an object, __________ a force must act to cause a change in the direction of the motion.

A．as
B．thus
C．so
D．like

单选题 Some companies have introduced flexible working time with less emphasis on pressure __________

A．than more on efficiency
B．and more on efficiency
C．and more efficiency
D．than efficiency