Obligation vs That's a pretty big commitment

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

Obligation

Top 2,000 (common)B2noun

That's a pretty big commitment

Top 5,000 (fairly common)
Most common: Obligation
 ObligationThat's a pretty big commitment
Pronunciation🇬🇧 /["/ˌɒblɪˈɡeɪʃn/"]/🇺🇸 /["/ˌɑːblɪˈɡeɪʃn/"]/🇬🇧 //ðæts ə ˈprɪti bɪg kəˈmɪtmənt//🇺🇸 //ðæts ə ˈprɪti bɪg kəˈmɪtmənt//
MeaningSomething you must do; a duty or responsibility.It's a significant promise or responsibility.
ExampleShe felt a strong obligation to help her friends in need.Buying a house really is a pretty big commitment.
RegisterNeutralNeutral
How commonTop 2,000 (common)Top 5,000 (fairly common)
CEFR levelB2-
Part of speechnoun
Collocationscontractual, legal, statutory, carry out, discharge, fulfil/​fulfill, arise from something, under an obligation, without obligation, obligation of, contractual, legal, statutory, carry out, discharge, fulfil/​fulfill, arise from something, under an obligation, without obligation, obligation ofmake a commitment, big commitment, long-term commitment, serious commitment, financial commitment
Antonymsfreedom, option, choice-
Common mistakesConfused with 'obligated' — remember 'obligation' is the noun., Using 'obligation' with incorrect prepositions — typically used with 'to' (e.g., obligation to pay)., Overusing in casual speech — more common in formal contexts.Using 'commitment' incorrectly as a verb instead of a noun., Confusing 'commitment' with 'agreement' - a commitment is more personal., Overusing 'pretty' in formal speech.
Usage notesUse 'obligation' in both formal and informal contexts when discussing responsibilities or duties. It's appropriate in legal, academic, or personal situations but less common in casual conversations.Use in contexts discussing promises or responsibilities, often when emphasizing importance. It’s suitable for casual conversations, but can be used in formal contexts if necessary.

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That's a pretty big commitment

Frequently asked questions: Obligation vs That's a pretty big commitment

What's the difference between Obligation and That's a pretty big commitment?

Obligation: Something you must do; a duty or responsibility. That's a pretty big commitment: It's a significant promise or responsibility.

Which is more common: Obligation and That's a pretty big commitment?

Obligation is the most common in everyday English.

Can you show an example of each?

Obligation: She felt a strong obligation to help her friends in need. That's a pretty big commitment: Buying a house really is a pretty big commitment.

Can I use Obligation and That's a pretty big commitment interchangeably?

Not always. Obligation and That's a pretty big commitment 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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