Cool MateSustainable vs Viable
When to use each in English, with meaning, register, and examples.
Sustainable
Top 2,000 (common)B2adjective
Viable
Top 2,000 (common)C1adjective
| Sustainable | Viable | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/səˈsteɪnəbl/"]/🇺🇸 /["/səˈsteɪnəbl/"]/ | 🇬🇧 /["/ˈvaɪəbl/"]/🇺🇸 /["/ˈvaɪəbl/"]/ |
| Meaning | Able to be maintained or continued without harming the environment. | Able to work or succeed. |
| Example | sustainable forest management | a **viable option/proposition** |
| Register | Neutral | Neutral |
| How common | Top 2,000 (common) | Top 2,000 (common) |
| CEFR level | B2 | C1 |
| Part of speech | adjective | adjective |
| Collocations | sustainable development, sustainable practices, sustainable energy, sustainable agriculture, sustainable living | be, prove, seem, extremely, truly, perfectly |
| Antonyms | unsustainable, destructive, nonrenewable | unviable, impractical, infeasible |
| Common mistakes | Confused with 'sustain' which means to keep something going., Using it incorrectly as an adverb (should be used as an adjective)., Mixing up 'sustainable' with 'sustained' which has a different meaning. | Confused with 'viable' vs 'viability' - remember 'viable' is the adjective., Using 'viable' incorrectly with non-project contexts, like personal opinions., Mixing up 'viable' with 'valid' - 'viable' relates to practicality, 'valid' to correctness. |
| Usage notes | Commonly used in discussions about the environment, business practices, and development. It is appropriate in both formal and informal contexts, but avoid using it in casual conversations if it doesn't fit the topic. | Use 'viable' when discussing options or plans that are practical and achievable. Avoid in very casual contexts; it sounds more professional. |
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Frequently asked questions: Sustainable vs Viable
What's the difference between Sustainable and Viable?
Sustainable: Able to be maintained or continued without harming the environment. Viable: Able to work or succeed.
Which is more advanced: Sustainable and Viable?
Viable is the highest level, at C1, on the CEFR scale.
Are Sustainable and Viable the same CEFR level?
Sustainable: B2, Viable: C1 on the CEFR scale.
What part of speech are Sustainable and Viable?
Sustainable: adjective, Viable: adjective.
Can you show an example of each?
Sustainable: sustainable forest management Viable: a **viable option/proposition**
Can I use Sustainable and Viable interchangeably?
Not always. Sustainable and Viable 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.