guard 和 secunrity guard分別

Security guard (not secunrity guard ) = 保安人員
Guard = 守衛;保護

We commonly use security guard when we refer it to a person's job.
e.g: Peter is the security guard of our company.

However,
we use "guard" normally as a verb,
for example,
A policeman kept guard over the prisoners.
However,
we may also use "guard" when we refer it to a person's job.

我推薦您一個非常不錯的英語學習網站，里面有很多非常不錯的學習資源：

http://www.hkenglishstudy.info

希望可以幫到你!

guard可以係解哨兵; 衛兵; 警備員; 看守員

secunrity guard靜係解保安員