I need to know which word is a gerund:

"Sleeping is an essential part of maintaining the body's health."

How can I tell which word is a gerund?

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http://www.chompchomp.com/terms.htm

Now -- scroll down to Gerund -- read and study. Then let me know what you decide.

To determine if a word is a gerund, you need to look for certain characteristics. A gerund is a verb form that functions as a noun, ending in -ing. In the given sentence, the word "sleeping" is a gerund. Here's how you can tell:

1. Identify the -ing form: Look for a verb that ends with -ing. In this case, it's "sleeping."

2. Test its function: A gerund acts as a noun, so replace the -ing word with a regular noun to check if the sentence still makes sense. In this case, let's replace "sleeping" with "activity." Now the sentence reads, "Activity is an essential part of maintaining the body's health." The sentence still makes sense, confirming that "sleeping" is indeed a gerund.

In summary, the word "sleeping" is a gerund since it ends with -ing and fulfills the function of a noun in the sentence.