What happened vs What was that

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

What happened

Top 2,000 (common)

What was that

Top 2,000 (common)
 What happenedWhat was that
Pronunciation🇬🇧 //wɒt ˈhæp.ənd//🇺🇸 //wɑt ˈhæpənd//🇬🇧 //wɒt wəz ðæt//🇺🇸 //wɑt wəz ðæt//
MeaningAsk someone about an event or situation.A question asking for clarification about something that happened.
ExampleCan you tell me what happened during the meeting?Did you hear that? What was that?
RegisterNeutralNeutral
How commonTop 2,000 (common)Top 2,000 (common)
Collocationswhat happened next, what happened then, can you tell me what happenedwhat was that noise, what was that sound, what was that about
AntonymsWhat will happen, What is going to happen, What occurs nextI understand, That is clear
Common mistakesConfused with 'what's happening?' which refers to current events., Using it to ask about an ongoing situation instead of a past event., Inappropriately using 'happened' in place of 'has happened' in some contexts.Confused with 'what is that?' which asks about something present., Used in formal situations where clarity is important., Overused in conversations, when direct questions could suffice.
Usage notesUse in conversations to inquire about past events. Suitable in both formal and informal settings.Use when you need to clarify something you didn't hear or understand. Avoid in formal presentations.

See it in real clips

What happened
What was that

Frequently asked questions: What happened vs What was that

What's the difference between What happened and What was that?

What happened: Ask someone about an event or situation. What was that: A question asking for clarification about something that happened.

Can you show an example of each?

What happened: Can you tell me what happened during the meeting? What was that: Did you hear that? What was that?

Can I use What happened and What was that interchangeably?

Not always. What happened and What was that 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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