你很仔细
这里确实是一个语法上的省略现象，than后面省略了主语what
在新概念英语第三册里的LESSON 29 funny or not 一课里面就有一句很类似的话
He drank more than was good for him
这句话也是省略了主语what 本来应该是He is often advised not to drink more wine than (what)is good for his health
第二个问题
present在这里作的成分是定语，修饰people
定语，通俗的讲就是修饰名词成分(主语，宾语...)的一个成分
也可以理解为一个定语从句的省略形式,省略了who are
There must have been several hundred people who are present.
内容全部来源于网络收集，如有侵权，请联系网站删除：QQ：24596024