I am like a gun. People use me to do their dirty work.

I am like a sword. There are two ends of me: the handle and the sharp sides

(sharp means literally for the sword and intelligent/wise metaphorically FYI)

I am like food. People take me for granted but there is no one in the world who can possibly live without me.

I am like a table. I have legs to support me, but I am the one supporting other things.

(Think about that one…that could be pretty clever if you think about it)

I am like a soldier. Even if a tough situation comes up I will keep trooping forward.

I am like history. What happens to me cannot be changed.

I am like the word orange. I am unique because nothing else sounds like me, or is like me at all.

I am like a metaphor. I have two meanings.

Again…if I come up with more I will post em here