Question

SAT语法题一道

Among the earliest telescopes were Galilean telescopes, modeled after the simple instruments built by Galileo, the first person （having used） telescopes to study the stars and planets.
答案说要把括号里的改成 to have used.这是为什么呢？我怎么觉得用having used 和to have used 没有区别？
谢谢~~

Answer 1

to have used是陈述事实，而having used表状态呢，这里不需要。不定式一般都优于其他形式，这是SAT的死变态潜规则……

Answer 2

having done 不能做定语

Answer 3

一般来说，序数词，后面接加的是不定式。