却步的英文：
to step back

参考例句：

Don't hang back in the face of difficulties.
不要因为困难而却步。

Still, should the scab of the sheep cause the shepherd to recoil?
可是羔羊的癣疥应当使牧人却步吗？

Jeremy was not deterred by this criticism.
杰里米没有因这一批评而却步。

Potential problem of celebrity status is not much of a determent to those seeking limelight.
成名带来的潜在问题不会使那些寻求名人地位的人却步。

step是什么意思：
n. 脚步；步态，步伐；步骤；措施；阶段，等级；台阶，平台；舞步
v. 踩，踏；跨步，行走；跳舞；使成阶梯状

step by step welding
跨步焊法

It is a step class.
这是踏板操训练班。

They are not in step with the times.
他们跟不上时代的步伐。

the execution of steps
舞步表演

To work step by step is as good as riding in a carriage.
安步当车

back是什么意思：
n. 后面，背面，反面；背，背部；靠背；后卫
v. 支持；后退，倒退；背书；下赌注于
adj. 背部的；后面的；过去的；拖欠的.
adv. 以前；向后地；来回地；上溯

Stand back to back!
背靠背站好！

They are on the back of the menu.
它们在菜单背面。

Our seats on the train were back to back.
我们在火车上的坐位是背靠背的。

It happened far back in the past.
这事发生在久远的过去。

the back of a Chinese robe or jacket
后襟