他们几乎脚尖踩着脚跟地挤作一团。用英语怎么说？

他们几乎脚尖踩着脚跟地挤作一团。

They were bunching up, almost treading upon each other's heels.

they

pron. 他/她/它们，人们，大家，政府，当局，她们；

例句
The storms had abated by the time they rounded Cape Horn.
他们绕过合恩角时，暴风雨已经减弱。

were

be的过去时复数和第二人称单数形式，有时代替 was,用于条件从句、动词 wish 之后等；

例句
Shops, houses, and vehicles were set ablaze.
店铺、房子和车辆全都陷于火海。

bunching

n. 聚束，成组，群聚；

例句
They were bunching up, almost treading upon each other's heels.
他们几乎脚尖踩着脚跟地挤作一团。

up

adv. 在上面，在高处，起床，起来，向上，由低到高；adj. 向上的，上升的，竖立的，垂直的，举起的；vt.& vi. 增加，加速，提高，举起，拿起；prep. 在…的上端，向高处，沿…而去，向…上游；n. 上升，升高，兴旺，繁荣，上坡，（价格等）上涨；

例句
Some parents believe a boy must learn to stand up and fight like a man.
有些父母认为男孩子必须学会像男子汉一样顶天立地，勇于抗争。

almost

adv. 几乎，差不多，将近，快要，近乎；

例句
Despite considerable pain she has been getting out and about almost as normal...
尽管还很痛，她已经基本上行动如常。

treading

v. 踩，踏( tread的现在分词 )，踩成，踏出，步行于；

例句
There are three reasons for treading warily in such matters.
这种事情需要谨慎行事有 3 个原因。

upon

prep. 在…上面，当…时候；

例句
...the doctrine of absolute monarchy based upon divine right.
以神权为基础的君主专制学说

each

adj. 每，各自的；pron. 每个，各自；

例句
They were completely absorbed in each other...
两人彼此倾心。

heels

n. 高跟鞋，紧随某人，跟捬，飞奔逃跑，（袜子等的）后跟( heel的名词复数 )，足跟，有…后跟的，女高跟鞋；

例句
I was very attracted to men and fell head over heels many times.
我很容易被男性吸引，曾多次深陷情网。