know their stuff

USAGE SUMMARY

"know their stuff" is a correct and commonly used expression in written English.
It means to have a good understanding or expertise in a particular subject or skill. Example: "The team of engineers hired for the project really knew their stuff. They were able to design and build an innovative solution in record time."

✓ Grammatically correct

News & Media

Formal & Business

Wiki

Human-verified examples from authoritative sources

Exact Expressions

60 human-written examples

"They know their stuff".

The New York Times

"And they know their stuff".

The New York Times

The two authors know their stuff.

The Economist

That means many residents know their stuff.

The Washington Post

They need to know their stuff.

The New York Times

The crowds at these events know their stuff.

The New York Times

Staff know their stuff and orders are handled speedily.

The Guardian - Books

Trust that people know their stuff and will execute.

Harvard Business Review

The staff know their stuff and can guide you.

The Guardian - Lifestyle

The staff are friendly and really know their stuff.

The Guardian - Lifestyle

Staff who know their stuff can help make decisions.

The Guardian - Travel

Expert writing Tips

Best practice

When writing for an international audience, consider if the idiom "know their stuff" translates well or whether a more universal expression of expertise would be more effective.

Common error

Avoid using "know their stuff" when describing general knowledge. This phrase is most effective when referring to specific, demonstrable skills or understanding within a particular field. Focus on being specific about the area where one "is knowledgeable".

Linguistic Context

The phrase "know their stuff" functions as a descriptive idiom, indicating that someone possesses significant knowledge or skill in a particular area. As Ludwig AI confirms, it is correct and commonly used in written English.

Expression frequency: Very common

Frequent in

News & Media

45%

Formal & Business

25%

Wiki

15%

Less common in

Science

5%

Encyclopedias

3%

Reference

2%

Ludwig's WRAP-UP

The phrase "know their stuff" is a common and grammatically sound idiom used to express that someone possesses significant expertise or knowledge in a specific domain. As confirmed by Ludwig AI, it's widely accepted and used across various contexts, though it leans toward an informal register. Usage analysis indicates that it's frequently found in news and media, formal business settings, and wiki content. While versatile, it's crucial to ensure the phrase aligns with the specific skills being highlighted to accurately convey expertise. For more formal scenarios, alternatives like "demonstrate expertise" or "possess extensive knowledge" may be more suitable.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

have mastery of

Emphasizes a complete and comprehensive understanding and skill.

be an expert

Emphasizes a high level of skill and knowledge in a specific field.

have expertise

Similar to 'be an expert' but focuses on the possession of expert knowledge.

be knowledgeable

Focuses on possessing knowledge, a core component of knowing one's stuff.

be well-versed in

Suggests extensive knowledge and familiarity with a particular subject.

be well-informed

Highlights the breadth of information possessed, suggesting a strong understanding.

have a good grasp of

Indicates a solid understanding and comprehension of a subject.

be proficient

Highlights skill and competence, suggesting mastery of a subject.

be skilled

Focuses on practical ability and competence in a particular area.

be competent

Highlights the ability to perform tasks effectively and skillfully.

FAQs

How can I use "know their stuff" in a sentence?

You can use "know their stuff" to describe someone's expertise in a particular area. For example, "The new marketing team really know their stuff and have already improved our campaign performance."

What are some alternatives to "know their stuff"?

Alternatives include "be knowledgeable", "be an expert", or "have expertise". The best choice depends on the specific context and the nuance you want to convey.

Is "know their stuff" formal or informal?

"Know their stuff" is generally considered informal but is acceptable in many professional contexts. For more formal writing, consider using phrases like "demonstrate expertise" or "possess extensive knowledge".

What does it mean when someone says "they really know their stuff"?

It means that the person or people in question have a deep understanding or a high level of skill in a particular area. It suggests competence and reliability.