"That she made" is the adjective clause. The words it modifies are "The suggestion"
An adjective clause has the following characteristics:
- It is a dependent clause (It can't stand alone as a full sentence): "That she made" does not express much on its own.
- It work as an adjective: The clause is giving details of what "Suggestions" we are talking about, that is to say, the words that it modifies are "The suggestions"
- It always begins with a relative pronoun (who, whom, whose, that, or which) or a relative adverb (when, where, or why). In this clause, "that" is the relative pronoun used.
- It has a verb: "made".
