循环回路的英文：
circulation loop
n. 血液循环；流通，传播；发行量
Have you been circulated with details of the conference?
你收到会议详情的通知了吗？
circulate counterfeit coins
使伪造的钱币流通
This magazine has a large circulation.
这本杂志发行量很大。
The circulation of gossip is abhorrent.
传播流言蜚语是可恶的。
The air was circulated mechanically.
空气循环是靠机械驱动的。
n. 环，圈；回路；弯曲部分；翻筋斗
v. 打环；以环连结；（使）翻筋斗
The airman looped the loop eight times.
那位飞行员作了八次翻筋斗的飞行表演。
The plane looped the loop three times.
飞机连翻了三个跟头。
Loop the tree with a rope = loop a rope around the tree
将绳子卷绕于树
Loop the curtains up.
把窗帘卷起来。
They looped the thing together.
他们用环将那些东西系在一起。