Question

---Why do you look so upset?
---There are so many troublesome problems ____.

A．remaining to be settled	B．remained settled
C．remaining to settle	D．remained to be settled

Answer 1

A

考察非谓语动词。根据句子结构可知，该处为problems的定语，remain是系动词，无被动。故排除BD. Remain的用法是sth remain to be done，
句意为，有很多麻烦的问题留待解决。