5.137 Indicating the start or end of a period

You can also indicate how long a situation lasts by using prepositional phrases to give the time when it begins or the time when it ends, or both.

If you want to talk about a situation that began in the past and is continuing now, or to consider a period of it from a time in the past to the present, you use the preposition 'since' with a time expression or an event to indicate when the situation began. The verb should be in the present perfect tense.

• I've been here since twelve o'clock.
• I haven't had a new customer in here since Sunday.
• Some 850 firemen have been laid off since April.
• I haven't been out since Christmas.
• He has not won a major championship since 1974.
• There has been no word of my friend since the revolution.

'Since' is also used to indicate the beginning of situations that ended in the past. The verb should be in the past perfect tense.

• I'd been working in London since January at a firm called Kendalls.
• He hadn't prayed once since the morning.
• I'd only had two sandwiches since breakfast.

'Since' can also be used with other prepositional phrases that indicate a point in time.

• I haven't seen you since before the summer.

The noun group after 'since' can sometimes refer to a person or thing rather than a time or event, especially when used with a superlative, 'first' or 'only', or with a negative.

• The last government was the greatest tragedy in our history since Henry the Eighth.
• I have never had another dog since Jonnie.