Where do we use since and for.give examples.
It is used to denote a specific period (or duration) of time. We can use ' for' with all the tenses.
I have been working for two hours.
He has lived in Mumbai for a long time.
It is used to denote the specify point an action or event begins (continuing till the point of speech). We use 'since' with perfect tenses.
I have been working since morning.
He has been living in Mumbai since 2010.
A period is a duration of time, for example: 5 minutes, 2 weeks, 6 years. For means "from the beginning of the period until the end of the period."
A point is a precise moment in time, for example: 9 o'clock, 1st January, Monday. Since means "from a point in the past until now." Since is normally used with perfect tenses.