Noun Clause

NOUN CLAUSE

   A noun clause is a dependent clause and cannot stand alone as a sentence.  It must be connected to an independent clause, a main clause. A noun clause has its own subject and verb. It can begin with a question word. It can begin with if or whether. And it can begin with that. 

a) Noun clauses with question words:

The following question words can be used to introduce a noun clause: when, where, why, how, who, whom, what, which, whose. 

Example:  

Answer this question using 'I don't know...'

Where does Maria live?

"I don't know where she lives" is the correct answer.

Noun clauses with who, what, whose + be:

A noun or pronoun that follows main verb 'be' in a question comes in front of 'be' in a noun clause. 

Example:
Who is that boy? I don't know who that boy is.

Whose pen is this? I don't know whose pen this is.

A prepositional phrase does not come in front of 'be' in a noun clause. 

Example:
Who is in the office? I don't know who is in the office.

Whose pen is on the desk? I don't know whose pen is on the desk.

b) Noun clauses, which begin with if or whether:

When a yes/no question is changed to a noun clause, if is usually used to introduce the clause.  

Example:

Is Maria at home?

               I don't know if Maria is at home.

Does this bus go to Los Angeles?

               I don't know if this bus goes to Los Angeles.

Did Juan go to Mexico?

               I wonder if Juan went to Mexico.

c) Noun clauses which begin with that: 

A noun clause can be introduced by the word 'that'.

I think that Ms. Weiss is a good teacher.

In the sentence above, 'Ms. Weiss is a good teacher' is a noun clause. It is the object of the verb 'think'.