1. TYPES OF CLAUSES
IN ENGLISH GRAMMER

2. What is a clause? A clause is a part of a sentence.
A clause is a group of words that has subject and predicate. Every complete sentence is made up of at least one or more clause(s). Following are clause examples:-
John bought a new car. (One sentence, one clause)
John bought a new car, but he is using his old car. (One sentence, two clauses)

3. Types of Clauses
Every clause has at least a subject and a verb. Clauses have some characteristics that help to distinguish one type of clause from another. Clauses are of following types:-
Independent Clauses (Main Clause)
Dependent Clauses (Subordinate Clause)
Relative Clauses (Adjective Clause)
Noun Clauses

4. Independent Clauses (Main Clause)
An independent (or main clause) is a complete sentence. It contains a subject and verb and expresses a complete thought in context and meaning. It expresses a complete thought.
Independent clause structure: Subject + Verb = Complete Thought.
For example: She walked. (This sentence contains only two words but it is still complete because it has subject and predicate)
Main clauses can be joined by a coordinating conjunction to form complex or compound sentences.
COORDINATING CONJUNCTIONS: and, but, for, nor, or, yet
For example: He bought new car but he is still using old one. "but" is used to combine two independent clauses.

5. Dependent Clauses (Subordinate Clause)
A dependent clause (or subordinate clause) is part of a sentence; it contains a subject and verb but does not convey complete sense. They can make sense on their own, but, they are dependent on the rest of the sentence for context and meaning. A dependent clause is joined to an independent clause to form a complex sentence. It often starts with a subordinating conjunction.

6. Dependent Clauses (Subordinate Clause)
SUBORDINATING CONJUNCTIONS
after
although as
because
before
even if
even though if
once
provided that
rather than
so that
since
though
than
that
until
unless
whenever
when
 whereas
where
whether
while
Dependent clause structure: Subordinate Conjunction + Subject + Verb = Incomplete Thought.
Examples: Whenever I go to superstore, I buy chips. .

7. Relative Clauses (Adjective Clause)
A relative clause starts with the relative pronoun at the start of the clause like who, which, whose etc. To make distinction between an antecedent that is a human "who(m)" and an antecedent which is a non-human "which". Following will make it clear further.
Who(m) is used when the antecedent is a person. That is used to refer to either a person or thing. Which is used to refer to anything except a person.
(It is noteworthy that whom is not used much in spoken English.)
Relative Clauses Examples 
I met my friends yesterday. The friend, who had curly hair, was very intelligent.
The race was the one that I lost.

8. Relative Clauses (Adjective Clause) RESTRICTIVE RELATIVE CLAUSES AND NON-RESTRICTIVE RELATIVE CLAUSES
Restrictive relative clauses are sometimes called defining relative clauses, or identifying relative clauses. Similarly, non-restrictive relative clauses are called non- defining or non-identifying relative clauses and is preceded by a pause in speech or a comma in writing.
Restrictive Clause Example:
The programmer who develops web applications will make a large profit.
Non-Restrictive Clause Example:
The programmer, who develops web applications, will make a large profit.

9. Relative Clauses (Adjective Clause) RESTRICTIVE RELATIVE CLAUSES AND NON-RESTRICTIVE RELATIVE CLAUSES
Restrictive
Non-restrictive
Human
Nonhuman
Subject
who, that
which, that
who
which
Object
who, whom, that
who, whom
After preposition
whom
Possessive
whose, of whom
whose, of which

10. Noun Clauses
Noun Clauses: It is a dependent clause that works as noun. Noun clauses can act as subject, direct or indirect objects or predicate nominatives. Some examples are as under:-
Tell me who left his book on the table. (direct object)
I shall tell whoever will listen my interesting story. (indirect object)
Whoever is the last one to leave turns off the lights. (subject)
The boy with the curled hair is who I want on my team. (predicate nominative)
Noun clauses often begin with pronouns or other words. That particular word usually has a grammatical function in the sentence

11. Noun Clauses Relative pronouns: that, what, who, which, whom, whose
Indefinite relative pronouns: whoever, whomever, whatever, whichever, whether, if
Interrogative adjective: what
Interrogative adverb: how
Interrogative pronoun: who
Subordinating conjunctions: whenever, how, when, if, where, whether, why