It's difficult to define the exact nature of the problem.

　　很難給這個問題確切定性。

　　Her second husband was the exact opposite of her first.

　　她的第二任丈夫與第一任截然不同。

　　Assessing insurance risk can never be an exact science.

　　估定承保的風險永遠不會成為一門精確的科學。

　　It happened late last century ─ in 1895 to be exact.

　　那事發(fā)生在上個世紀末——確切地說，發(fā)生在1895年。

　　What is the exact location of the ship?

　　那條船的確切位置在哪里？