1. Since shows where we start counting
In its time meaning, since means “from a particular moment onwards”. We look back to the start of a period, while the main statement covers the time up to now.
The starting point need not be an exact date. It can be a morning, a holiday, childhood or an event familiar to the listener.
The past participle is the form used with have/has. For regular verbs, we usually add -ed; learn irregular forms separately: know → known, see → seen, be → been.
have / has + past participle + since + starting point
- V3 / past participle —
- The third verb form: worked, gone, seen. Used after have/has or in the passive, for example; it is not always the same as V2.
I have had this desk since April.
I have had this desk since April.
April is the start of the period of possession; I still have the desk.
We have known each other since childhood.
We have known each other since childhood.
Childhood gives a point of reference in our lives, rather than an exact day.
2. A starting point and a duration answer different questions
Since Monday names the start. For three days measures the length of the period. To choose between them, read the whole expression after the preposition, rather than just the number.
Three years is a duration; three years ago is a point three years in the past. This makes since three years ago possible. For three years is often simpler in an ordinary statement about duration, but since three years ago is not a grammatical error.
The shop has been closed since Monday.
The shop has been closed since Monday.
The sentence names the day from which the shop has not been open.
The shop has been closed for three days.
The shop has been closed for three days.
The sentence names the length of the period, rather than its start.
I have not used that account since three years ago.
I have not used that account since three years ago.
Three years ago identifies a past starting point. For three years instead expresses the length of that period; both can describe the same interval here.
3. An event instead of a date
After since, you can use a whole clause stating who did what. Past Simple is a useful choice for a completed event marking the start: since I arrived.
Do not treat this pattern as a ban on other tenses. Present Perfect is also possible after since, particularly for a state that continues. The choice depends on the meaning; at this stage, we mainly practise clear starting events.
Main statement + since + subject + verb
- subject / S —
- The grammatical subject: who or what the clause is about; the verb agrees with it. In The book was written, the book is the subject, although someone else does the action.
- verb / V —
- A word for an action or state, such as work or be. The pattern determines its form.
I have cooked at home since I moved here.
I have cooked at home since I moved here.
Moved identifies the move as the event from which the habit began.
Since I have been here, I have met several neighbours.
Since I have been here, I have met several neighbours.
Have been describes being here as a continuing state; this is a valid clause after since.
4. States, repeated events and events that have not happened
Present Perfect with since can describe a state continuing until now, several events during an unfinished period, or something that has not happened during that period. Since itself does not mean an uninterrupted action every second.
Use has with he / she / it, and have with I / you / we / they. The auxiliary needs a past participle after it: known, seen, been, rather than knew, saw, was.
She has been a nurse since 2021.
She has been a nurse since 2021.
This describes her professional status up to now, rather than working without a break.
We have visited the museum twice since it opened.
We have visited the museum twice since it opened.
We sum up two separate visits, rather than an uninterrupted stay.
I have not seen my neighbour since Friday.
I have not seen my neighbour since Friday.
The negative covers the time from the starting point on Friday until now.
5. Bringing the starting point into a conversation
An answer to How long…? can name either a duration or a starting point: Since January. This short reply is natural when the context is clear.
If an event has already been mentioned, since then means “from that time onwards”. The event in the preceding sentence gives then a specific point of reference. You can ask a question with Have / Has to check a suggested date.
How long have you had this phone? — Since January.
How long have you had this phone? — Since January.
A question about the length of possession can be answered with its starting point.
The lift broke on Tuesday. It has not worked since then.
The lift broke on Tuesday. It has not worked since then.
Then refers back to the event on Tuesday.
Has Leo lived here since 2020?
Has Leo lived here since 2020?
Has comes before the subject; the date remains a starting point.
6. The limits: since does not always refer to time
Since can also mean “because”, introducing a reason. Such a sentence does not necessarily need Present Perfect. Check the meaning, rather than automatically reacting to the word.
This lesson focuses on time-related since and a connection to the present. Other constructions exist, including reference to the past with Past Perfect, but they are not the target here. In your own writing, you can combine the target sentence with other appropriate tenses.
Since the room is small, we need fewer chairs.
Since the room is small, we need fewer chairs.
The small size is the reason for the decision; no starting point of a period is given.
The room has been empty since the class ended.
The room has been empty since the class ended.
The end of the class is a time reference; empty describes the state continuing until now.
Common mistakes
Incorrect:I have had this bike since four years.
Correct:I have had this bike for four years.
Four years is the length of a period. Since needs a starting point, such as since 2022 or since four years ago.
Incorrect:She have lived here since May.
Correct:She has lived here since May.
She needs has in Present Perfect; since May names the start.
Incorrect:We have knew Sam since school.
Correct:We have known Sam since school.
Have needs the past participle known, rather than the past form knew.
Incorrect:I have lived here from I was ten.
Correct:I have lived here since I was ten.
Before the clause I was ten in this meaning, use since, rather than from.