Idiom B1

Kill two birds with one stone

Achieve two things with a single action

Meaning

Kill two birds with one stone — To accomplish two different tasks or goals with a single action, saving time and effort.

Origin & History

The phrase has been in use since at least the 17th century in English. It appears in a 1656 work by Thomas Hobbes. The image refers to a hunter throwing one stone and hitting two birds at once.

Example Sentences

SentenceContext
I'll kill two birds with one stone by picking up the kids and stopping at the supermarket.Efficient errands
Taking an online course while working kills two birds with one stone.Self-improvement and career
The new policy kills two birds with one stone: reducing costs and improving morale.Business context

How to Use It

Neutral. Works in conversation, semi-formal emails, and persuasive writing. Common in professional discussions about efficiency.

Common Mistakes

Mistakes to Avoid

We can kill two birds with one stone and do both things.

We can kill two birds with one stone. — 'And do both things' is redundant; the idiom already says that.

Let's kill two birds with one stone of this meeting.

Let's kill two birds with one stone in this meeting. — Use 'in', not 'of', or simply omit the prepositional phrase.

Similar Idioms

Two for oneHit two targets at onceBe efficient All Idioms →

Practise This Idiom

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Frequently Asked Questions

What does "Kill two birds with one stone" mean?
"Kill two birds with one stone" means achieve two things with a single action. To accomplish two different tasks or goals with a single action, saving time and effort.
Where does the idiom "Kill two birds with one stone" come from?
The phrase has been in use since at least the 17th century in English. It appears in a 1656 work by Thomas Hobbes. The image refers to a hunter throwing one stone and hitting two birds at once.
Can you give an example of "Kill two birds with one stone" in a sentence?
Here is an example: "I'll kill two birds with one stone by picking up the kids and stopping at the supermarket." — used when efficient errands.
Is "Kill two birds with one stone" formal or informal?
Neutral. Works in conversation, semi-formal emails, and persuasive writing. Common in professional discussions about efficiency.
What CEFR level is "Kill two birds with one stone"?
This idiom is typically taught at B1 level. It is a intermediate expression that appears in a wide range of spoken and written English contexts.
What are common mistakes with "Kill two birds with one stone"?
The most common mistake is getting the articles wrong. Always use the fixed form of the idiom without changing the words. For example: We can kill two birds with one stone. — 'And do both things' is redundant; the idiom already says that.
What idioms are similar to "Kill two birds with one stone"?
Similar idioms include: Two for one, Hit two targets at once, Be efficient. These share the same general meaning but may differ slightly in tone or context.
How do I practise idioms like "Kill two birds with one stone"?
LexFizz's Flip Tiles and Flash Cards exercises are great for practising English idioms. Try to write your own example sentences using the idiom in context, and listen for it in films, podcasts, and conversations.
Can "Kill two birds with one stone" be used in writing?
Yes, but it depends on the register. Neutral. Works in conversation, semi-formal emails, and persuasive writing. Common in professional discussions about efficiency. Idioms generally work best in spoken English or informal writing; avoid them in formal academic or professional documents unless you are sure of your audience.
Does "Kill two birds with one stone" have the same meaning in British and American English?
Yes, "Kill two birds with one stone" is understood in both British and American English with the same meaning: achieve two things with a single action. Some idioms vary between dialects, but this one is widely recognised in all major varieties of English.