at the back of something, often hidden
The sun was hidden behind the clouds.
太阳被云层遮挡住了。
falling short of progress or schedule
We're behind schedule because of the delay.
由于延误,我们落后于计划了。
supporting or approving of someone or something
Her family was right behind her decision.
她的家人完全支持她的决定。
responsible for the creation or development of something
She was the mastermind behind the successful project.
她是成功项目背后的策划者。
in the past, no longer a concern
The mistake is behind you, don't dwell on it.
错误已经过去,不要纠结了。
further back or at the back
She walked behind the line of trees.
她走在一排树的后面。
remaining in a place after others have left
Her keys were left behind on the table.
她的钥匙忘在桌子上了。
later than the due date or expected time
He is behind in his payments.
他拖欠付款了。
a polite way to refer to someone's buttocks
He sat down hard on a rock and hurt his behind.
他重重地坐在石头上,伤到了臀部。