Final answer:
The four restrictive clauses found in the sentences are: who owns a red car, that ate my homework, that have cherries, and that she gave them. These clauses are essential to the meaning of the sentences they modify.
Step-by-step explanation:
The clauses in the passage that are restrictive include:
- (a) The girl who owns a red car is the one we are looking for.
- (b) The dog that ate my homework is called Henry.
- (c) I’m saving the muffins that have cherries for my sister.
- (d) The smile that she gave them was beautiful.
These clauses are considered restrictive because they limit the identity of the nouns they modify and are essential for the meaning of the sentence.