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Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
i realised why
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "I realised why" is correct and usable in written English.
You can use it when you want to express that you have come to an understanding or insight about a particular reason or cause. Example: "After reflecting on the situation for a while, I realised why my friend was upset with me."
✓ Grammatically correct
News & Media
Formal & Business
Science
Alternative expressions(6)
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Human-verified examples from authoritative sources
Exact Expressions
20 human-written examples
That's where I realised why I'm proud to be British.
News & Media
Afterwards I realised why I was receiving some very odd looks (Letters, 28 May).
News & Media
I realised why while reading William Gibson's 2003 novel Pattern Recognition.
News & Media
Watching Körper again in the Barbican's Bite series, I realised why.
News & Media
I realised why pantomime has developed such a bad name among more cautious parents.
News & Media
I haven't watched Holby City or Casualty for many years – and I realised why after this episode.
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
40 human-written examples
Now I realise why.
News & Media
Having just seen ad I realise why people are mad.
News & Media
"Now I realise why people call second albums difficult.
News & Media
"When I watch BBC1, I realise why we're not on it," reasons Fielding.
News & Media
From the first bite of the dosai, I realise why my friends have been raving about this place.
News & Media
Expert writing Tips
Best practice
Use "i realised why" to express a newfound understanding or insight. It's often used to explain a previous confusion or a change in perspective.
Common error
Avoid using present tense like "i realise why" when describing a past realization. Use the past tense "realised" to accurately reflect the moment of understanding.
Source & Trust
89%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "i realised why" functions as a causal connector, introducing an explanation for a previously unclear situation. Ludwig shows examples in various contexts, indicating its versatility.
Frequent in
News & Media
70%
Formal & Business
15%
Science
10%
Less common in
Encyclopedias
2%
Wiki
1%
Reference
2%
Ludwig's WRAP-UP
The phrase "i realised why" is a common and grammatically correct way to introduce an explanation or newfound understanding, as validated by Ludwig. It functions as a causal connector and is primarily used in news, media, and business contexts. While versatile, it's important to use the correct tense (past tense "realised" for past realizations) and choose appropriate synonyms based on the context and desired nuance. Examples provided by Ludwig demonstrate the phrase's broad applicability and contribute to a deeper understanding of its use.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
i understood the reason
Replaces "realised" with a more direct synonym "understood" and "why" with "the reason", resulting in a more explicit statement.
i came to understand why
Emphasizes the process of understanding, suggesting a gradual realization.
i figured out the reason
Uses the phrasal verb "figured out" to convey a sense of solving a puzzle or mystery.
i now understand the reason
Adds emphasis on the current understanding, contrasting with a previous lack of understanding.
the reason became clear to me
Shifts the focus to the reason itself becoming clear, rather than the speaker's action of realizing.
the penny dropped
An idiomatic expression meaning to suddenly understand something.
it dawned on me why
Uses the idiom "dawned on me" to indicate a sudden realization or understanding.
i grasped the reason
Uses the verb "grasped" to indicate understanding, implying a firm or complete understanding.
i apprehended why
Uses the more formal verb "apprehended" to indicate understanding, suggesting a deeper level of comprehension.
i discerned the reason
Uses the verb "discerned" to imply careful observation and deduction in understanding the reason.
FAQs
How can I use "i realised why" in a sentence?
You can use "i realised why" to introduce an explanation for something you previously didn't understand. For instance, "After seeing her reaction, "i realised why" she was so upset."
What are some alternatives to "i realised why"?
Alternatives include "i understood the reason", "i came to understand why", or "it dawned on me why", depending on the specific nuance you wish to convey.
Is it correct to say "i realize why" instead of "i realised why"?
The use of "i realize why" implies a current or ongoing realization, while "i realised why" refers to a past realization. Both are grammatically correct, but their appropriate use depends on the context.
What's the difference between "i realised why" and "i found out why"?
""i realised why"" suggests an internal understanding or insight, whereas "i found out why" implies gaining information from an external source.
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Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
89%
Authority and reliability
4.5/5
Expert rating
Real-world application tested