往复的英文：
to reciprocate

Reciprocating screw
往复螺杆

Back and forth; to and fro
来回地;往复地

Move up and down or to and fro
上下或往复移动

the to - and - fro of a pendulum
钟摆的往复摆动

Up-and-down or to-and-fro motion
上下或往复的移动

Single movement to and fro when equilibrium has been disturbed
(偏离平衡位置的)一次往复振动

(of parts of a machine)move alternately backwards and forwards in a straight line
(指机件)沿直线往复移动

A holding pressure unit allows the pre-plasticizer or a reciprocating screw to plasticize during the long holding time.
保压装置使预熔器或往复螺杆在冗长的保压时间内加料。

"To music slow, then quick, following his hand, Now far away, now near again, according to his heart."
言迟更速皆应手,将往复旋如有情。

"If air compressor is reciprocating type, Check Valves shall be downstream of receiver tank."
如果空气压缩机是往复型,则止回阀应该位于接受槽的下游位置。

They have a reciprocal loathing for each other.
他们互相憎恨。

Reciprocal affection,help,trade
互爱、互助、互惠贸易

The piston is reciprocating inside cylinder.
活塞在汽缸内部往复运动。

The degree of recombination is reciprocal in most cases
重新结合的程度在大多数情况下是相互的。

Courtesy requires reciprocity among neighbors.
乡里之间讲究礼尚往来。