back down
back off
To give up a claim; not follow up a threat.
Bill said he could beat Ted, but when Ted put up his fists Bill backed down.
Harry claimed Joe had taken his book, but backed down when the teacher talked with him.
back of
in back of
In or at the rear of; to the back of; behind.
The garage is back of the house.
Our car was in back of theirs at the traffic light.
Being a cause or reason for; causing.
Hard work was back of his success.
The principal tried to find out what was back of the trouble on the bus.
In support or encouragement of; helping, clones will be elected because many powerful men are back of him.
Get in back of your team by cheering them at the game.
break the back of the beast
Дословно: сломать спину чудовищу.
Преодолеть какие-то значительные трудности.
Преодолеть какие-то значительные трудности.
He finally broke the back of the beast and passed his driving exam!
Он преодолел все трудности и сдал экзамен на права!
eyes in the back of one's head
Ability to know what happens when your back is turned.
Mother must have eyes in the back of her head, because she always knows when I do something wrong.