Important vs That's the key for him

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

Important

Top 1,000 (very common)A1adjective

That's the key for him

Top 5,000 (fairly common)
Most common: Important
 ImportantThat's the key for him
Pronunciation🇬🇧 /["/ɪmˈpɔːtnt/"]/🇺🇸 /["/ɪmˈpɔːrtnt/"]/🇬🇧 //ðæts ðə kiː fɔː hɪm//🇺🇸 //ðæts ðə kiː fɔr hɪm//
MeaningSomething that matters a lot.It's important for him.
ExampleIt's important to drink enough water every day.That's the key for him to succeed in his career.
RegisterNeutralNeutral
How commonTop 1,000 (very common)Top 5,000 (fairly common)
CEFR levelA1-
Part of speechadjective
Collocationsbe, seem, sound, extremely, fairly, very, for, to, be, seem, sound, extremely, fairly, very, for, tokey to success, key factor, key element, key issue, key player
Antonymsunimportant, trivial, insignificant-
Common mistakesConfusing with 'unimportant'—'not important' is the opposite., Using with nouns incorrectly—'important' only describes nouns, not verbs., Overusing—try varying language with synonyms to improve vocabulary.Confused with 'that's key for him' without 'the', Using 'the key to him' inaccurately, 'Key' misused as a physical object instead of meaning important
Usage notesUse 'important' for things that have significance or impact. It's appropriate in formal and informal contexts, but in very casual conversation, words like 'big deal' might be more appropriate.Commonly used to indicate something vital to a person's success or understanding. Usually informal in speech, but can be used in writing.

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Important
That's the key for him

Frequently asked questions: Important vs That's the key for him

What's the difference between Important and That's the key for him?

Important: Something that matters a lot. That's the key for him: It's important for him.

Which is more common: Important and That's the key for him?

Important is the most common in everyday English.

Can you show an example of each?

Important: It's important to drink enough water every day. That's the key for him: That's the key for him to succeed in his career.

Can I use Important and That's the key for him interchangeably?

Not always. Important and That's the key for him 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.

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