他们的手指在一起勾着。用英语怎么说？

他们的手指在一起勾着。

Their fingers intertwined.

their

pron. 他（她，它）们的，在提及性别不详的人时，用以代替 him 或 her；

例句
Their permissiveness toward their children reflects the wild abandon of their own lives.
他们对孩子的放任折射出他们自身生活的放浪形骸。

fingers

n. 手指( finger的名词复数 )，指状物，指幅，（手套的）指部；

例句
Yulka's fingers were bloody and cracked.
尤尔卡的手指折断了，鲜血直流。

intertwined

v. 缠结在一起( intertwine的过去式和过去分词 )；

例句
The towels were embroidered with their intertwined initials.
毛巾上绣着他们姓名首字母的连写组合。