邮费的最低收费是5美元。

There is a ___minimum charge of $5 for postage.

进入大多数夜总会的最低年龄是18岁。

Eighteen is the ___minimum age for entering most nightclubs.

那是大多数语言学校教授英语所需的最低学位。

That's the ___minimum degree required to teach English in most language schools.