What part of speech is the word but?

The word "but" can be a few different parts of speech, depending on its function in a sentence. Here's a breakdown:

* Conjunction: This is the most common use. It connects words, phrases, or clauses, often expressing contrast or opposition.

* Example: "I wanted pizza, but he wanted tacos."

* Preposition: This is less common, and it usually means "except" or "aside from."

* Example: "I love all fruits but bananas."

* Adverb: This is even rarer, and it usually means "only" or "merely."

* Example: "He's but a child."

To determine which part of speech "but" is in a particular sentence, consider its function and the context of the sentence.