What does an adjective clause tell?

What does the adjective clause modify in the sentence?

I want a jacket that zips up the front.

An adjective clause is almost always introduced by a...

What is the adjective clause in the sentence?

The girl whose name I don't remember let me borrow a pencil once.

What is the adjective clause in the sentence?

Hannah, the girl whom I admire, got nominated as student of the month for our class.

What is the adjective clause in the sentence?

Stephen Hawking, who grew up disabled since the age of 20, made many notable discoveries in the field of science.

What is the relative pronoun that begins the adjective clause?

The table company that we purchased from forgot to add in the screws.