When learning or improving English, one of the most common sources of confusion for non-native speakers is understanding the correct use of time expressions. A particularly puzzling phrase for many is for since how long. This phrase often appears in casual conversation or while forming questions about the duration of an action or event. Understanding its meaning, structure, and correct usage is essential for speaking and writing English accurately and naturally. This topic will explore the meaning of for since how long, how it relates to the individual words for, since, and how long, and how they are used properly in grammar.
Understanding the Parts: For, Since, and How Long
Meaning of For
The word for is used to indicate a duration of time. It answers the question: how long has something happened? It is followed by a period of time.
- Examples:
- I have lived hereforfive years.
- She waitedforthree hours.
In each example, for precedes a specific duration and emphasizes the length of the time span.
Meaning of Since
Since is used to refer to a specific point in time in the past. It tells us when something started, and it implies that the action or condition still continues up to the present.
- Examples:
- He has worked heresince2010.
- They have been friendssincechildhood.
Unlike for, which deals with duration, since marks the starting point of an action.
Meaning of How Long
How long is used when asking about the duration of time something has been happening or will happen. It introduces a question about time.
- Examples:
- How longhave you been studying English?
- How longwill the meeting last?
How long is compatible with both for and since, depending on what the speaker wants to express.
Is For Since How Long Correct?
The phrase for since how long is grammatically incorrect in standard English. It combines three separate time expressions that are not used together in a single phrase. While it might seem logical to use all three to express curiosity about duration and starting point simultaneously, English grammar does not support this structure. Instead, we choose either for or since depending on the context of the question or statement.
Correct Forms and Examples
- How longhave you lived here? (General question about time)
- For how longhave you lived here? (More formal, same meaning)
- Since whenhave you lived here? (Focuses on the starting point)
So, instead of saying for since how long, one should use either for how long or since when depending on the emphasis duration or starting time.
Using For in Questions
Structure and Application
To ask about the duration of something, use the pattern:
For how long + auxiliary verb + subject + main verb?
- For how long have you been waiting?
- For how long did they study in that school?
- For how long will the program continue?
This structure is clear and standard. It is acceptable in both spoken and written English.
Using Since in Questions
Structure and Application
To find out the starting point of an action, use:
Since when + auxiliary verb + subject + main verb?
- Since when have you been working here?
- Since when did you know about the event?
Since when usually implies that the event is still happening or relevant. It often has a sense of surprise or curiosity attached to it.
Differences Between For and Since
Duration vs Starting Point
The key difference lies in the focus:
- For= duration (e.g., for three weeks, for two hours)
- Since= starting point (e.g., since Monday, since 2001)
Examples to highlight the difference:
- I have been herefortwo hours. (Emphasizes length of time)
- I have been heresince10 AM. (Emphasizes start of action)
Common Mistakes Learners Make
Mixing For and Since Incorrectly
Some English learners confuse for and since or try to use them together, leading to phrases like for since how long or since two hours, which are incorrect.
- Incorrect: I have known him since two years.
- Correct: I have known himfortwo years.
- Incorrect: For since how long have you been here?
- Correct: How longhave you been here?
Using How Long with the Wrong Tense
How long is often used with present perfect or present perfect continuous tense to indicate actions that started in the past and are still ongoing.
- Correct: How long have you been working here?
- Incorrect: How long do you work here?
The correct tense helps express time more accurately and naturally.
Tips to Remember Correct Usage
- Useforwith periods of time: minutes, hours, days, weeks, years.
- Usesincewith a specific point in time: yesterday, last week, 2015, Monday.
- Askfor how longto know the duration.
- Asksince whento know the starting point.
Though the phrase for since how long may appear in speech or writing from non-native speakers, it is grammatically incorrect and should be avoided. Understanding the individual meanings of for, since, and how long helps construct clear and accurate time-related questions and statements. By mastering these basic but important grammatical tools, learners can improve both their written and spoken English. Clarity in communication depends on using the right expressions in the right way, and learning when to say for how long or since when is a step toward that clarity. Keep practicing with real-life examples, and you’ll build confidence in using these expressions correctly.