A clause is a group of words that includes a subject and a verb but is not a complete sentence.

An antecedent is the noun or pronoun that a pronoun replaces in a sentence.

An antecedent clause is a clause that a pronoun replaces in another part of the sentence.

Example:

There was great confusion. A mouse running under the table caused people to jump and run from it.

• The pronoun 'it' takes the place of the noun clause 'a mouse running under the table'.

Subordinate or dependent clause is a group of words which contains a subject and a verb which can not stand on its own.

Example: I went to see a movie which was running in a theatre near my house. (In this sentence, I went to see a movie is an independent clause that stands on its own, whereas the second part of the sentence, which was running in a theatre near my house, is a subordinate clause which can not stand on its own as it does not give complete information.