When you say "mind" you are saying "be aware of" or "be careful with" not to be confused with "beware of".
They might overlap, depending on why you may want to be aware of something. You might need to "mind the dog" because he bites or you might need to "mind the dog" because you are about to absent-mindedly step on it's tail.
"Beware of your head" is strange sounding. "Mind your head" means to be careful with your head. "Beware of" in this context implies that your head is going to do something bad to you, whereas "mind your head" is meant to say be careful not to let something bad happen to your head.
I don't see the words as being extremely similar.
Smug is exhibiting or feeling great or offensive satisfaction with oneself or with one's situation; self-righteously complacent, where synonyms are self-satisfied, superior, complacent, conceited, self-righteous, holier-than-thou, priggish, self-opinionated. The stress is on the self-righteous attitude accompanying being pleased with oneself.
While I know that complacent means satisfied with how things are and not wanting to change them, I think the connotation is one of unawareness of actual dangers or deficiencies in oneself or something one is a member of, for example, a political party or a church
I think, for example, that much of the world has become complacent about AIDS. We just don't worry about it as we once did.
Condescending means showing or characterized by a patronizing or superior attitude toward others, showing that you believe you are more intelligent or better than other people.
Best Answer
"Together" specifies that "close" is referring to those two things. "McDonalds and KFC are close together" means they are next to each other. "McDonalds and KFC are close" means they are both within easy walking distance of where we are now.
However, it is different with people. "Mac and Kay are close" means those two people have a good friendship. "Mac and Kay are together" probably refers to a sexual relationship, but if you say "Mac and Kay are close together" you are back to saying they are next to each other, adjacent desks maybe.