竟然用英文怎么表达？

　　They were caught in a clinch when their parents returned home unexpectedly.

　　父母突然回家，撞见他俩拥抱在一起。

　　Miserable, and unexpectedly lonely, she went in search of Jean-Paul

　　内心痛苦、突感寂寞的她去寻找琼－保罗。

　　She panics when people pop in unexpectedly, rushing round plumping cushions.

　　一群人冷不防地冒出来，跑来跑去地拍松垫子，这把她吓坏了。

　　A new force ( e.g. a school of thought, etc.) emerged unexpectedly.

　　异军突起。

　　I meant to help him; unexpectedly I have brought him trouble.

　　我想帮助他，没想到反而给他添了麻烦。