why you are late
what you want
where you want to stay
how you go there
how many people there are in the school
2. Noun +which/who/that/+Subject+Verb
a flower that/which I like
the song which/that Mr. Smith sang yesterday
Jasmine who I love
Mr. Smith who is my brother
the dog which/that was killed yesterday
the flower that is on the table
These clauses are "noun". Therefore you can use in the "subject position" and "object position".
I want to know what you want.
What I want is a car.
Jasmine who I love is my class-mate.
She is Jasmine who I love.
The flower that is on the table is rose.
I like the flower that is on the table.
I think there are other caluses.
That's all I know now.
Student or Learner