The use of since/for.
We use the present perfect to say how long something has continued up to now.We can say how long with 'since' or 'for'.
-We use since when we give the beginning of the time.(for example:since Wednesday)
-We use for when we give the length of the time.(for example:for two days).
Examples:
Since:
I have worked here since 2004.
I have had this car since October.
I have known your parents since 1978.
For:
I have worked here for three years.
I have had this car for three months.
I have known your parents for a long time.(or for 29 years)
For - Since
English Grammar Rules
The use of FOR
We use For when we measure the duration – when we say how long something lasts.
For + a period of time
To measure a period of time up to the present, we use the present perfect tense and not the present tense.
- I have known her for a long time. (Correct)
- I know her for a long time. (Incorrect)
- I have lived here for ten years. (Correct)
- I live here for ten years. (Correct)
The present tense with For refers to a period of time that extends into the future.
- How long are you here for? (Until when)
- How long have you been here for? (Since when)
In reality, we can use all verb tenses with For.
Uses of For | |
Example sentence | Verb Tense |
They exercise for two hours every day. | Present tense |
They are exercising for three hours today. | Present continuous |
He has lived in Moscow for a long time. | Present perfect |
He has been living in Turin for three months. | Present perfect continuous |
I worked at the service station for five years. | Past tense |
He will be in hospital for at least a week. | Future tense |
However, we don't use For with expressions such as all day or all the time.
- I was there all day. (Correct)
- I was there for all day. (Incorrect)
The use of SINCE
Since gives the starting point of actions, events or states. It refers to when things began.
Since + a point in time (in the past), until now.
- I've been waiting since 7 o'clock.
- I have known him since January.
With since we use the present perfect tense or the past perfect tense.
- I have been here since 5 o'clock and I am getting tired.
- I had been working since 5 o'clock and I was getting tired.
Since can also be used in the structure It has been + period of time + since.
- It has been two months since I last saw her.
- It has been three years since the last earthquake.
For vs. Since
Knowing when to use FOR and when to use SINCE is important. Therefore it is useful to look at a summary of the contrast between FOR and SINCE.
FOR to mention a specific period (or duration) of time. | SINCE to mention the starting point of a period of time (continues to now). |
I have been a doctor for fifteen years. (duration = 15 years) | I have been a doctor since 1992. (starting point = 1994) |
She has been a mother for six months. | She has been pregnant since her first child was born. |
My sister has lived in Frankfurt for nine months. | My sister has lived in Frankfurt since the beginning of March. |
Both For and Since are most commonly used with the perfect tense - we don't use these expressions in the present tense.
Correct | Incorrect |
I have learnt Russian for three years. | I learn Russian for three years. |
They have taught geography since last year. | They teach geography since last year. |
He has owned his dog since his cat died. | He owns his dog since his cat dies. |
While we can use For in the simple past tense we can't use Since in the simple past tense. Since can only be used in the perfect tense.
Correct | Incorrect |
She went to Japan for three years. | She went to Japan since 2003. |
I studied in New Zealand for one month. | I studied in New Zealand since one month. |
He walked his dog for four hours. | He walked his cat since four hours. |
It should be remembered that both For and Since have other meanings in English that are not associated with time.
- This is for you.
- Is this the train for London?
- Since you asked, I'll say yes.
- Since he didn't study he didn't pass the exam.
Adverbs of Frequency
English Grammar Notes
We use some adverbs to describe how frequently we do an activity.
These are called adverbs of frequency and include:
Frequency | Adverb of Frequency | Example Sentence |
100% | always | I always go to bed before 11pm. |
90% | usually | I usually walk to work. |
80% | normally / generally | I normally go to the gym. |
70% | often* / frequently | I often surf the internet. |
50% | sometimes | I sometimes forget my wife's birthday. |
30% | occasionally | I occasionally eat junk food. |
10% | seldom / rarely | I seldom read the newspaper. |
5% | hardly ever | I hardly ever drink alcohol. |
0% | never | I never swim in the sea. |
* Some people pronounce the 'T' in often but many others do not.
The Position of the Adverb in a Sentence
An adverb of frequency goes before a main verb (except with To Be).
Subject + adverb + main verb |
I always remember to do my homework. |
He normally gets good marks in exams. |
An adverb of frequency goes after the verb To Be.
Subject + to be + adverb |
They are never pleased to see me. |
She isn't usually bad tempered. |
When we use an auxiliary verb (have, will, must, might, could, would, can, etc.), the adverb is placed between the auxiliary and the main verb. This is also true for to be.
Subject + auxiliary + adverb + main verb |
She can sometimes beat me in a race. |
I would hardly ever be unkind to someone. |
They might never see each other again. |
They could occasionally be heard laughing. |
We can also use the following adverbs at the start of a sentence:
Usually, normally, often, frequently, sometimes, occasionally
- Occasionally, I like to eat Thai food.
BUT we cannot use the following at the beginning of a sentence:
Always, seldom, rarely, hardly, ever, never.
We use hardly ever and never with positive, not negative verbs:
- She hardly ever comes to my parties.
- They never say 'thank you'.
We use ever in questions and negative statements:
- Have you ever been to New Zealand?
- I haven't ever been to Switzerland. (The same as 'I have never been Switzerland').
We can also use the following expressions when we want to be more specific about the frequency:
- every day - once a month - twice a year - four times a day - every other week
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