The suffix -ing attaches to the end of verbs to create new words with different jobs in a sentence.

When you add -ing to a verb, you often create what's called a present participle, which shows an action happening right now or continuously. “I am reading” tells us the reading is happening at this moment. “The singing bird” describes a bird in the act of singing.

But -ing does more than that. It can turn a verb into a noun called a gerund, transforming an action into a thing you can talk about. “Swimming is fun” treats swimming as an activity you can enjoy. “I love baking” makes baking into something you can love, just like you might love baseball or music.

Sometimes -ing words work as adjectives: a running stream, a growing problem, an exciting discovery. The word describes what something is doing or what it's like.

You use -ing words constantly without thinking about it. “I was thinking about going hiking after finishing my homework” contains four -ing words, each doing a different job. This tiny suffix is one of the hardest-working tools in English, letting you describe ongoing actions, create nouns from verbs, and build complex, interesting sentences.