Sofia's throat had tightened and she couldn't speak...是什么意思？

Sofia's throat had tightened and she couldn't speak...

索菲娅喉咙哽住了，说不出话来。

throat

n. 咽喉，颈前部，[植物学]管颈；vt. 用沙哑的声音或嗓音发音；

had

v. 有（ have的过去式和过去分词 ），（亲属关系中）接受，拿，买到；

tightened

v. 收紧( tighten的过去式和过去分词 )，（使）变紧，（使）绷紧，加紧；

and

conj. 和，与，而且，于是，然后，因此；

she

pron. 她，它；

speak

vt.& vi. 讲，谈，演说，从某种观点来说；