A compound noun, verb, adjective, preposition etc., is one that is made of two or more parts. The meaning of a compound is not always predictable from the meanings of its component parts.
Examples are: bus-driver, girlfriend, put up with, green-hued, looking forward to etc.
Not every friend who is a girl is your girlfriend.
Not every board which is black is a blackboard.
How do you put up with him?
A sentence which contains two or more main clauses, but no subordinate clauses. The clauses in a compound sentence are connected by a conjunction like and, or, but, or yet.
In the following examples the main clauses are bracketed.
(Ann smokes) but (Mary doesn’t).
Ann wrote the letters) and (Peter posted them).
A noun which denotes something which is physical and can be touched.
Examples are: dog, plastic, grass, boy and brother.
The label conditional refers to that form of a verb made by using the modal auxiliary verb would (also should in the first person). The name is given because sentences with these auxiliaries often seem to imply an unstated condition.
I would like a drink.
I would run.
She would sing.
I should think.