The word "rush" can be used as a noun or a verb. As a noun, it refers to a sudden movement or activity. As a verb, it means to move quickly or with urgency.
Sudden is an adjective.
The word "you" belongs to the pronoun word class, particularly as a second person singular pronoun. It is used to refer to the person or people being spoken to.
Ornithologist.
preposition
The word "saw" can be both a verb (past tense of see) and a noun (a tool used for cutting).
It falls into the action category
The word "rush" can be either a verb or a noun, depending on how it is used in a sentence.
it's a preposition
Adjective
Sudden is an adjective.
If you mean the part of speech, it is a noun. If you mean the etymology, it comes from Greek.
The word "you" belongs to the pronoun word class, particularly as a second person singular pronoun. It is used to refer to the person or people being spoken to.
Ornithologist.
Tigers belong to Class Mammalia.
Opossums belong to the class mammalia.
Sea fans belong to the class Anthozoa
A piranha belong to the Phylum Chordata, and the class Osteichthyes.