Understanding the difference
The phrases look similar, but they’re used differently in English sentences.
1) a long time ago
This is the common, standard way to say that a lot of time passed before something happened in the past. We use the article a and the adjective long together before time.
- We went to the castle a long time ago.
- She learned to ride a bike a long time ago.
2) long time ago (without 'a')
Without the article a, this phrase is less common and can sound incomplete. It might appear in headlines, notes, or informal speech as a shorthand, but is generally not the standard form in full sentences.
- Standard: a long time ago.
- Less common: long time ago (usually requires context or a different sentence structure).
Practical rules
- Always use a before long time when forming a full sentence: a long time ago.
- Avoid long time ago as a standalone phrase in regular sentences; keep a for standard usage.
- In short notes or headlines, you might see Long time ago with capitalization and no article, but this is not standard grammar for full sentences.
Examples
- Correct: A long time ago, people traveled by horse and carriage.
- Correct: It happened a long time ago.
- Incorrect in full sentence: Long time ago people traveled by horse and carriage.