There is a security guard at the entry.

入口处有一名保安。

There is a security guard at the entrance.

入口处有一个保安。

The presence of a security guard is reassuring.

有保安在场是令人安心的。

The thief masquerade as a security guard to gain access to the vault.

小偷伪装成保安以进入金库。

A security guard was killed in the bank raid.

这次银行劫案中有一名保安员遇害。

A security guard is among five people arrested.

被逮捕的五人中有一名是保安。

So, for example, a security guard is walking around the building. There's other security guards.

例如，一个保安正在大楼周围走动。那里还有其他保安。

He looked like a security guard. So I just approached him.

可能是保安吧。所以我接近他。

If you are a security guard, you probably cannot telecommute .

如果你是个保安，那你可能就没法远程办公了。

All authorized access points for visitors are staffed by a security guard.

所有的经认可的通路访客的点被一个保安人员配备人员.