What part of speech is the word crossing?

The word "crossing" can be a few different parts of speech, depending on how it's used in a sentence:

* Noun: This is the most common usage, referring to the act of going across something.

* Example: "They took a crossing on the ferry."

* Verb: It can be the present participle of the verb "to cross."

* Example: "The birds were crossing the sky."

* Adjective: It can describe something that crosses.

* Example: "The crossing guard helped the children."

* Gerund: It can be a noun formed from a verb, acting as the subject or object of a sentence.

* Example: "Crossing the street can be dangerous."

To determine the part of speech, you need to look at the context of the sentence and how the word is being used.