Cool MateThat'd be why vs That's why
When to use each in English, with meaning, register, and examples.
That'd be why
InformalTop 2,000 (common)
That's why
Top 1,000 (very common)
Most formal: That's whyMost common: That's why
| That'd be why | That's why | |
|---|---|---|
| Pronunciation | 🇬🇧 //ðæt wəd bi waɪ//🇺🇸 //ðæt wəd bi waɪ// | 🇬🇧 //ðæts waɪ//🇺🇸 //ðæts waɪ// |
| Meaning | This phrase explains a reason for something. | This is the reason. |
| Example | I couldn't find my keys this morning. That'd be why I was late. | The project was delayed. That's why we need an extension. |
| Register | Informal | Neutral |
| How common | Top 2,000 (common) | Top 1,000 (very common) |
| Collocations | that'd be why, that'd be the reason, so that'd be why | that's why I, that's why we, that's why she, that's why they, that's why he |
| Common mistakes | Overuse in formal settings where a different explanation is needed., Incorrectly used as a standalone answer without context. | 'That's why' is sometimes confused with 'that's because', which has a slightly different use., Learners often forget to follow 'that's why' with a clear explanation., Some may use 'that's why' in overly formal contexts, where a more precise term is needed. |
| Usage notes | Used in casual conversations to indicate that the situation makes sense. Avoid in formal writing. | Use 'that's why' to explain or justify a statement. It's suitable for conversation and informal writing, but may be less formal in essays. |
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Frequently asked questions: That'd be why vs That's why
What's the difference between That'd be why and That's why?
That'd be why: This phrase explains a reason for something. That's why: This is the reason.
Which is more formal: That'd be why and That's why?
That's why is the most formal of these.
Which is more common: That'd be why and That's why?
That's why is the most common in everyday English.
Can you show an example of each?
That'd be why: I couldn't find my keys this morning. That'd be why I was late. That's why: The project was delayed. That's why we need an extension.
Can I use That'd be why and That's why interchangeably?
Not always. That'd be why and That's why 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.