What Does “Base sth on sth” Mean?
“Base sth on sth” means to use something as the foundation or reason for making a decision, judgment, or action. It shows that one thing depends on or is supported by another.
Introduction
The phrase “base something on something” is a common English expression used to explain how one idea, decision, or action depends on another. Understanding the “base sth on sth” meaning is essential for clear communication, especially when explaining reasons or sources of information. For example, you might base your opinion on facts or base a story on real events. This phrase helps show the connection between cause and effect or the source of an idea. It is often used in daily conversations, writing, and professional contexts to express how one thing is built upon or influenced by another.
Quick Info Box
- Phrasal verb: base something on something
- Type: transitive
- Level: B1 (Intermediate)
- Short meaning: to use one thing as the foundation for another
Structure (Grammar Rules)
The phrasal verb “base sth on sth” is separable. You can place the object “something” between “base” and “on,” or after “on.”
- base something on something (common and formal)
- base on something (less common but correct when object is clear)
Examples of patterns:
- Subject + base + object + on + object
- Subject + base + on + object (if no direct object)
How to Use “Base sth on sth”?
Use “base sth on sth” when you want to explain that one thing depends on or is created from another. It is often used in academic, business, and everyday contexts. For example, you can base a decision on research, base a story on facts, or base your opinion on experience. This phrase helps clarify the source or foundation of ideas, actions, or judgments.
Examples
- She based her conclusion on the latest scientific data.
- The movie is based on a true story from the 19th century.
- We need to base our plans on the current budget.
- His argument was based on incorrect information.
- Can you base your decision on the facts rather than emotions?
Here is “base sth on sth” in a sentence: “The teacher based the lesson on the students’ prior knowledge.”
Common Mistakes
- Incorrect: I base on my experience the decision.
Correct: I base the decision on my experience. - Incorrect: The story based on real events.
Correct: The story is based on real events. - Incorrect: Base your opinion from facts.
Correct: Base your opinion on facts.
Differences / Synonyms
Similar expressions include “depend on,” “rely on,” and “build on.” However, “base sth on sth” specifically means to use something as a foundation or source, often in a formal or logical sense. “Depend on” suggests reliance but not necessarily as a foundation. “Build on” implies adding to something already existing, while “base on” focuses on the starting point.
Common Collocations
- base a decision on
- base an opinion on
- base a story on
- base a plan on
- base research on
- base a theory on
- base judgment on
Related Phrasal Verbs
Here are related phrasal verbs of base sth on sth:
Real-life Dialogue
Anna: How did you decide which candidate to hire?
Tom: I based my decision on their experience and skills.
Anna: That makes sense. Did you also consider their references?
Tom: Yes, I based part of my judgment on the references as well.
Practice
Fill in the blanks with the correct form of “base sth on sth”:
- We should _______ our marketing strategy _______ the latest customer data.
- The novel is _______ a famous historical event.
- Can you _______ your argument _______ solid evidence?
- Her opinion is _______ personal experience.
FAQs
- What does “base sth on sth” mean? It means to use one thing as the foundation or reason for another.
- Is “base sth on sth” separable? Yes, the object can come between “base” and “on.”
- Can I say “base on” without an object? Usually, you need an object after “base” or after “on” to make the meaning clear.
- What are some common collocations with “base sth on sth”? Common collocations include base a decision on, base a story on, and base an opinion on.
- Is “base sth on sth” formal? It is neutral and suitable for both formal and informal contexts.

