请帮忙分析一个英文句子的语法成分原句是 Others were able to wait what,for them,must have seemed an endless 20 minutes.在这个句子里,what 以后的部分是wait后面的宾语重句吗?what 在这里具体作用是什么?

what 接在wait 后引导宾语从句。for them 插入语，them 指代前面的others. what 在右面句子中作主语。翻译是：有一些人，对于他们来说，能够等需要等20多分钟的事。

原句是 Others were able to wait what, for them, must have seemed an endless 20 minutes. 在这个句子里，what 以后的部分是wait后面的宾语重句吗？what 在这里具体作用是什么？谢谢
答：本题句法分析并不难，难的是句意的理解和翻译。
要正确理解，需要有上下文。经搜索，发现本句（实为半句）摘自：新视野大学英语读写教程第四册Unit10
Children were told that they could have a single treat, such as a piece of candy, right now. However, if they would wait while the experimenter ran an errand, they would have two pieces of candy. Some preschoolers grabbed the treat immediately, but others were able to wait what, for them, must have seemed an endless 20 minutes.
分析：主语：others
谓语：were able to wait
宾语（从句）：what, for them, must have seemed an endless 20 minutes.
从句分析：
主语：what
谓语 must have seemed (系动词的情态式）
表语：an endless 20 minutes
状语（插入语）：for them
译：一些学前儿童立刻去急抓那颗糖，另一些却能等上那，对他们而言，一定很漫长的20分钟。
这相were able to 除了“过去能够”外，更有succeeded in (doing sth.)/ managed to do sth.的意思。
要译出不易。

是宾语从句，what在宾语从句中担当主语成分。

其他人能够等待他们的是什么，必须有似乎无穷无尽的20分钟
从翻译的结果看，what在这里引导了宾语从句

划分句子成分有助于理解句意：【Others主语】【 were able to wait 谓语】【 what,for them,must have seemed an endless 20 minutes 宾语】要翻译,也可以将句子结构调整：【Others主语】【 were able to wait 谓语...