It is easy to construct a sentence having a noun clause. One way is to begin a sentence like this:

He says that …

Whatever clause you put after ‘that’ will automatically become a noun clause.

• He says that he is ill.
• He says that he is coming.
• He says that he has won a prize.
• He says that it is raining.

Instead of say you can use any of the following verbs:

know, believe, think, realise, feel, hope, understand, wish, see, notice, find, discover, note, hear, listen, say, tell, ask, request, order, explain, suggest, reply, inform

• I knew that she was ill.
• I believe that he will pass.
• I understand that you are in great trouble.
• I wish that I understand his motive.
• She suggested that I should consult a doctor.
• I heard that she was going to act in a film.

Related posts:

1. Noun clause
2. Uses of a noun clause
3. Clauses
4. Complex and Compound-complex sentence
5. Noun: Gender
6. Nouns in Apposition
7. Noun: Number