Difficult vs Not so easy

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

Difficult

Top 1,000 (very common)A1adjective

Not so easy

Top 3,000 (common)
Most common: Difficult
 DifficultNot so easy
Pronunciation🇬🇧 /["/ˈdɪfɪkəlt/"]/🇺🇸 /["/ˈdɪfɪkəlt/"]/🇬🇧 //nɒt səʊ ˈiːzi//🇺🇸 //nɑt soʊ ˈizi//
MeaningHard to do or understand.Something that is not simple or straightforward.
ExampleThis math problem is really difficult.Completing this project on time is **not so easy**.
RegisterNeutralNeutral
How commonTop 1,000 (very common)Top 3,000 (common)
CEFR levelA1-
Part of speechadjective
Collocationsbe, look, prove, extremely, fairly, very, be, look, prove, extremely, fairly, verynot so easy task, not so easy to understand, not so easy as it seems, not so easy decision
Antonymseasy, simple, straightforward-
Common mistakes'Difficult' is often confused with 'hard.', Some learners use 'difficult' in place of 'complicated.', Misplacing 'difficult' in a sentence, like saying 'it's difficult to me' instead of 'it's difficult for me.'Use 'not so easy' in formal writing where it's too informal., Confuse with 'not easy' - 'not so easy' implies a comparison., Overuse in contexts where simpler phrases would suffice.
Usage notesUse 'difficult' when describing tasks, problems, or situations that require a lot of effort. Avoid in very casual conversations; instead, use synonyms like 'hard.'Used to express that a task or situation is more difficult than it appears. Often used informally in conversation.

See it in real clips

Difficult
Not so easy

Frequently asked questions: Difficult vs Not so easy

What's the difference between Difficult and Not so easy?

Difficult: Hard to do or understand. Not so easy: Something that is not simple or straightforward.

Which is more common: Difficult and Not so easy?

Difficult is the most common in everyday English.

Can you show an example of each?

Difficult: This math problem is really difficult. Not so easy: Completing this project on time is **not so easy**.

Can I use Difficult and Not so easy interchangeably?

Not always. Difficult and Not so easy 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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