他们得付出沉重的代价。用英语怎么说？

他们得付出沉重的代价。

They had to pay rather heavily.

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。

had

v. 有（ have的过去式和过去分词 ），（亲属关系中）接受，拿，买到；

例句
He claimed that his parents had abandoned him...
他声称父母遗弃了他。

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。

pay

vt.& vi. 付款，偿还，补偿，（对…）有利；vt. 给予，支付；n. 工资，薪水，报答；adj. 收费的，需付费的；

例句
Single people are treated as an aberration and made to pay a supplement.
独身者被当成异类，而且要付一笔额外的费用。

rather

adv. 稍微，有点，相当，颇，宁愿，相反地；int. 当然啦，怎么不；

例句
These wines may taste rather hard and somewhat acid.
这些酒可能喝着比较冲并且有股酸味。

heavily

adv. 在很大程度上，沉重地，大量地，缓慢又高声地；

例句
The killer must have been heavily bloodstained.
凶手肯定身上血迹斑斑。