What context can I use each word in?
Learn when and how to use these words with these examples!
keep
Example
I need to keep this book for reference. [keep: verb]
Example
It's important to keep your room clean and tidy. [keep: verb]
Example
I keep in touch with my family by calling them every week. [keep: verb]
sustain
Example
The company needs to sustain its growth to remain competitive. [sustain: verb]
Example
We need to sustain the ecosystem by reducing pollution. [sustain: verb]
Example
The athlete sustained an injury during the game. [sustained: past participle]
Good things to know
Which word is more common?
Keep is more common in everyday language, while sustain is more formal and often used in technical or academic contexts.
What’s the difference in the tone of formality between keep and sustain?
Sustain is more formal than keep and is often used in technical or academic contexts.
