They were frightened of being double-crossed.是什么意思？

They were frightened of being double-crossed.

他们害怕被骗。

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。

frightened

adj. 害怕的，受惊的；v. （使）惊恐( frighten的过去式和过去分词)，吓唬；

例句
I was too tired and frightened to find comfort in that familiar promise.
我既疲惫又恐惧，就连那熟悉的承诺都无法让我感到安慰。

of

prep. 关于，属于…的，由…制成；aux. 助动词 [非标准用语、方言] =have [主用于虚拟语气]；

例句
He did have a real knowledge of the country...
他对该国的确知之甚多。

being

n. 存在，生物，人，要素，本质；

例句
...expensive make-up that we saw being advertised by a beautiful model...
我们所见的由一位漂亮模特代言的昂贵化妆品