In English, many root words can be used in multiple forms. For example:

I play guitar.  Play is a verb.

I am a guitar player. Player is a noun.

The kitten is playful. Playful is an adjective.

The kitten acts playfully.  Playfully is an adverb.

In the sentence “I pet my pet”, which word is the verb and which is the noun?  The first ‘pet’ is the verb, or petting action, followed by the noun, or animal ‘pet’.

What about “I love love”?  

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