Sustain vs You're trying to keep her alive

When to use each in English, with meaning, register, and examples.

Sustain

Top 2,000 (common) C1 verb

You're trying to keep her alive

Top 2,000 (common)

	Sustain	You're trying to keep her alive
Pronunciation	🇬🇧 /["/səˈsteɪn/","/səˈsteɪnz/","/səˈsteɪnd/","/səˈsteɪnɪŋ/"]/ 🇺🇸 /["/səˈsteɪn/","/səˈsteɪnz/","/səˈsteɪnd/","/səˈsteɪnɪŋ/"]/	🇬🇧 //jʊəːr ˈtraɪɪŋ tə kiːp hɜːr əˈlaɪv// 🇺🇸 //jʊr ˈtraɪɪŋ tə kip hɜr əˈlaɪv//
Meaning	To keep something going or maintain it.	You want to make sure she stays alive.
Example	We must find ways to sustain our natural resources for the future.	In the middle of the storm, you're trying to keep her alive by finding shelter.
Register	Neutral	Neutral
How common	Top 2,000 (common)	Top 2,000 (common)
CEFR level	C1	-
Part of speech	verb
Collocations	no longer, barely, indefinitely, be able to, can, be unable to	keep someone alive, try to keep alive, keep alive an idea
Antonyms	neglect, abandon, cease	-
Common mistakes	'Sustain' is often confused with 'sustained' as a past form., Learners sometimes forget to add an object after 'sustain'., 'Sustain' is misused when referring to temporary situations, instead of ongoing support.	Confusing 'keep alive' with 'keep alive' in technical contexts., Using 'you' instead of 'one' in formal writing., Not clarifying who 'her' refers to in complex sentences.
Usage notes	Use 'sustain' in contexts about keeping something alive or supporting it over time. It can be formal when discussing topics like environmental issues or less formal in conversations about personal interests.	Use in situations involving emergencies or critical care. Suitable for serious contexts but avoid in casual conversations.

See it in real clips

"And I might share with you some words which have sustained me

Sherlock › S1 E1

Impossible to sustain a smoking habit in London these days.

There's not a planet in our solar system that could sustain life...

"And I might share with you some words which have sustained me

Sherlock › S1 E1

Impossible to sustain a smoking habit in London these days.

Sustain

You're trying to keep her alive. You can't let her go.

You're trying to keep her alive

Frequently asked questions: Sustain vs You're trying to keep her alive

What's the difference between Sustain and You're trying to keep her alive?

Sustain: To keep something going or maintain it. You're trying to keep her alive: You want to make sure she stays alive.

Can you show an example of each?

Sustain: We must find ways to sustain our natural resources for the future. You're trying to keep her alive: In the middle of the storm, you're trying to keep her alive by finding shelter.

Can I use Sustain and You're trying to keep her alive interchangeably?

Not always. Sustain and You're trying to keep her alive are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.