临行的英文：
before leaving; on departure

参考例句：

I left in such a hurry that I didn't have time to say good-bye to you
临行匆忙,未能向你告别。

"Carefully she sews and thoroughly she mends, Dreading the delays that will keep him late from home. "
临行密密缝,意恐迟迟归。

before是什么意思：
prep. 在…之前；优于，先于；当面
conj. 在…之前
adv. 先前，从前

Rain before seven;fine before eleven
雨过天晴

They corned their horses before the journey.
他们在启程前用玉米喂马。

The army was arrayed before the commander.
部队在指挥官前列好阵势。

leaving是什么意思：
v. [leave] 的现在分词形式；离开；留下

To leave;vacate.
离开；撤出

I leave that to you.
这都留给你啦。

Leaves die, fall, and shrivel.
叶子凋零、飘落枯萎了。

departure是什么意思：
n. 离开；出发；违背；辞职

The cold weather antedated their departure.
寒冷的天气使他们提前离开。

We apologise for the late departure of this flight.
本航班延误离境，谨致歉意。

His sudden departure was a disadvantage to the campaign.
他的突然离去对竞选造成不利影响。