入内的英文：
Intro

No entry
不准入内

No admission
请勿入内

Dogs not allowed
禁止带犬入内

The electric plant is off limits.
电厂是禁止入内之地区。

Children under 12 will not be admitted
十二岁以下的儿童不得入内

He was processed through the security network before being allowed in.
他经安全系统检查后方被准许入内。

No admittance;no admission
禁止入内

Keep out
请勿入内

Strictly no admittance
严禁入内

No entrance without a permit.
没有许可证不准入内。

There's an intro of eight bars before you come in.
你在八小节的前奏之后加入。

And sometimes in my intro classes that's the approach that I take.
有时候，在我的介绍课上，我采用这种方法。