他们被获许通婚。用英语怎么说？

他们被获许通婚。

They were allowed to intermarry...

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。

allowed

adj. [计]容许的；v. 允许( allow的过去式和过去分词 )，承认，酌增，接受；

例句
He was not allowed access to a lawyer.
他未被获准见律师。

to

prep. 向，朝着，到，关于，属于；adv. 朝一个方向的，到某种状态，关闭；

例句
I suggest you leave it to an expert...
我建议你把它留给专家来解决。

intermarry

vi. 不同种族[国家、教派]间的通婚，近族通婚，近亲结婚；

例句
The priestly caste does not normally intermarry with the warrior caste.
教士阶级通常不与武土阶级通婚.