I know then

USAGE SUMMARY

"I know then" is a correct and usable phrase in written English.
It is used to indicate an understanding at a specific moment in time. For example, "I heard the news and I know then that my efforts had paid off."

✓ Grammatically correct

News & Media

Academia

Science

Human-verified examples from authoritative sources

Exact Expressions

47 human-written examples

"Yes, I know, then you were lying," finished Matt.

Harvard Business Review

But little did I know then that her betrayal was a blessing in disguise.

The New Yorker

Little did I know then that it would lead to the next step in my career.

Massachusetts Institute of Technology

Did I know then what the flower generation was or what the sexual revolution meant?

The Guardian - Opinion

How could I know then that my working life as an actor would be so tied up with her?

The Guardian

May I know, then, what is the future for developing countries, mired in corruption, poverty and religious fundamentalism?

The Guardian

Human-verified similar examples from authoritative sources

Similar Expressions

13 human-written examples

I knew then.

The New York Times - Sports

"And I knew then.

The New York Times - Magazine

I knew then they were proper bullets".

The New York Times

I knew then our relationship was over.

The New York Times

I knew then where I was going.

The Guardian - Books

Expert writing Tips

Best practice

Combine “I know then” with a specific detail about what was understood to improve readability and maintain a reader's engagement.

Common error

Avoid using "I know then" to describe a current state of knowledge. This phrase is specific to a past realization. For current knowledge, use "I know now" or simply "I know".

Linguistic Context

The primary grammatical function of "I know then" is to act as an adverbial phrase indicating a specific point in time when understanding was achieved. It connects a past event with a subsequent realization. Ludwig provides examples showing this temporal connection.

Expression frequency: Uncommon

Frequent in

News & Media

40%

Academia

30%

Science

30%

Less common in

Formal & Business

0%

Encyclopedias

0%

Wiki

0%

Ludwig's WRAP-UP

In summary, the phrase “I know then” is a grammatically correct and usable expression that pinpoints a past moment of understanding or realization. Ludwig indicates the phrase is valid. It is most frequently found in news articles, academic writing, and scientific publications suggesting a neutral register. While not exceedingly common, the phrase serves a useful purpose in narrative, providing context and clarity. When using "I know then", be mindful of maintaining correct tense and aiming for the right balance of formality for your target audience.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

I realized at that moment

Emphasizes the realization aspect more explicitly.

I understood at that time

Replaces "know" with "understood" for a slight shift in emphasis.

At that point, I was aware

Uses "aware" to highlight the state of being informed.

That's when I understood

Rearranges the sentence structure to emphasize the timing.

It became clear to me then

Focuses on the clarity gained at that time.

Only then did I understand

Adds emphasis on the delay before understanding.

I came to understand then

Highlights the process of reaching understanding.

I grasped it then

Uses "grasped" to suggest a quick understanding.

At that instant, I knew

Emphasizes the immediacy of the understanding.

I perceived it then

Uses "perceived" to suggest an intuitive understanding.

FAQs

How can I use "I know then" in a sentence?

Use "I know then" to describe a moment in the past when you gained understanding or awareness about something. For example, "I heard the news, and "I know then" that my hard work had finally paid off".

What's the difference between "I knew then" and "I know then"?

"I knew then" implies a past state of knowing, while "I know then" describes the moment of becoming aware. "I knew then" focuses on possessing knowledge, whereas ""I know then"" highlights the instance of understanding.

What are some alternatives to "I know then"?

You can use phrases like "I realized at that moment", "I understood at that time", or "at that point I was aware" to convey a similar meaning, focusing on the moment of understanding.

Is "I know then" appropriate for formal writing?

While grammatically correct, ""I know then"" might sound less formal than alternatives like "I then understood" or "It became clear to me at that time". Consider your audience and the overall tone when choosing the phrase.