They won't let him leave the country.

他们不许他离开这个国家。

《牛津词典》

He would not be allowed to leave the country.

他不准离开这个国家。

《柯林斯英汉双解大词典》

They cannot leave the country without permission.

没有许可他们不得离开这个国家。

《柯林斯英汉双解大词典》

Fifty-thousand U.S.troops will leave the country at the end of August, with the remaining by the end of next year.

VOA: standard.2010.03.08

A statement from the U.S.Embassy in Bishkek says it will not give shelter to the president nor help him leave the country.

VOA: standard.2010.04.12

(Speaking in Russian) Marituu says the understanding of Estonians and many others is that, after liberating Estonia from the Nazis, the Soviet Army somehow forgot to leave the country.

VOA: standard.2009.12.25

Fathi Bahavi(ph) has two sons in college, one of whom wants to leave the country.

NPR: Iran Facing Dangerous Brain Drain

Mrs Z won a High Court action allowing her husband to help her leave the country.

BBC: 'My brother chose to end his suffering'

Some Greeks say they are making plans to leave the country if the situation worsens.

WSJ: Ahead of Vote, Greeks Move Cash, Hire Guards