Since vs For vs From
Three prepositions. One Hindi word (से). Thousands of wrong answers every year in SSC CGL and IBPS PO. This page fixes that permanently.
The One-Line Rule
Side-by-Side Comparison
| Feature | SINCE | FOR | FROM |
|---|---|---|---|
| Meaning | Starting point in time | Length of duration | Start of a range (needs end) |
| Follows | Perfect tenses only | Any tense | Any tense |
| Paired with | Nothing — stands alone | Nothing — stands alone | TO / TILL / UNTIL |
| Answers | "When did it start?" | "How long?" | "From when — to when?" |
| Example | since 2019 / since Monday / since she left | for 5 years / for three hours / for a long time | from 9 to 5 / from Jan to March |
SINCE — Point in Time
Always answers: “When did it start?”
Rules:
- 1. Always used with perfect tenses: Present Perfect, Past Perfect, Present Perfect Continuous.
- 2. Followed by a specific point: a year (since 2019), a day (since Monday), a named event (since independence), or a clause (since she left).
- 3. Never followed by a duration word (an hour, three days, a long time) — that's FOR's job.
- 4. Can introduce a subordinate clause: “since we were in school.”
✅ Correct Examples
She has been living here since 2015.
I have not seen him since last Tuesday.
It is the best film I have seen since Lagaan.
We have been friends since we were in school.
FOR — Duration
Always answers: “How long?”
Rules:
- 1. Used with any tense — Perfect (ongoing) or Simple (completed).
- 2. Followed by a duration: for 5 years, for three hours, for a long time, for ages, for two weeks.
- 3. Duration words = number + unit, or vague quantities: a long time, ages, a while, many years.
- 4. With Perfect tense → action still ongoing. With Simple tense → action is complete.
✅ Correct Examples
She has been studying for six hours. (still studying)
He worked there for 20 years and then retired. (completed)
I have not slept for two days.
They waited for a long time before giving up.
FROM — Start of a Range
Always answers: “From when to when?” — needs a paired end-point.
Rules:
- 1. FROM must always be paired with TO, TILL, or UNTIL — it cannot stand alone as a time preposition.
- 2. Used for schedules, routines, and ranges: office hours, exam timing, historical eras.
- 3. Used with any tense — past, present, future, simple or continuous.
- 4. Not interchangeable with SINCE in Perfect tense sentences where no end-point is given.
✅ Correct Examples
The office is open from 9 a.m. to 6 p.m.
She studied law from 2018 to 2023.
Children learn fastest from birth to the age of five.
The exam will be held from 10 a.m. till 1 p.m.
🇮🇳 The Hindi “से” Trap — Why Indian Students Get This Wrong
In Hindi/Urdu, the single postposition से (se) covers the meanings of SINCE, FOR, and sometimes FROM. So:
Hindi → Incorrect English → Correct English
“Main 2019 se yahan hun” → “I am here from 2019.” → “I have been here since 2019.”
“Main teen ghante se wait kar raha hun” → “I am waiting since three hours.” → “I have been waiting for three hours.”
Fix: Translate mentally, then check — is it a point in time or a duration? Point → SINCE · Duration → FOR.
Decision Flowchart
e.g. from Monday to Friday
+ Perfect or Simple tense
+ Perfect tense only
🎯 The 4 Classic Exam Traps
These exact error patterns appear in SSC CGL, CHSL, and IBPS PO every year. Memorise the correction and the reason — the reason is often the exam question.
I have been waiting since three hours.
✅ I have been waiting for three hours.
📌 'Three hours' is a duration → FOR. SINCE needs a point in time, never a number + unit.
She has been working here from 2020.
✅ She has been working here since 2020.
📌 '2020' is a year — a specific starting point. In a Perfect tense sentence without a paired end-point, use SINCE, not FROM.
He is absent since last Monday.
✅ He has been absent since last Monday.
📌 Two errors: (1) 'is' should be 'has been' — SINCE demands Perfect tense. (2) Even if (1) were fixed, SINCE is correct for 'last Monday'. Both errors together are a common Tier-I trap.
I will work from 2 p.m. since 6 p.m.
✅ I will work from 2 p.m. to 6 p.m.
📌 FROM pairs with TO / TILL, never with SINCE. SINCE is for starting points in perfect tense, not for giving the end of a future schedule.
🔑 Examiner's Trick Box
- ▸ If you see SINCE in the sentence but the following word is a number + unit (since three days, since two hours) — it is always wrong. Change to FOR.
- ▸ If you see FROM with a perfect tense but no end-point — it is always wrong. Change to SINCE.
- ▸ “The longest/best/first … since [event]” is a fixed superlative + SINCE pattern — always Present Perfect.
- ▸ FOR can be used with Simple Past for completed actions. SINCE cannot. “He lived there for 5 years” is correct. “He lived there since 2010” is wrong (needs perfect tense).
- ▸ “Suffer FROM a disease” — here FROM is a preposition of cause, not time. Do not confuse it with the time preposition FROM. Context determines the role.