USE OF ALREADY,YET,FOR AND SINCE IN PRESENT PERFECT
USE OF ALREADY,YET,FOR AND SINCE IN PRESENT PERFECT Using the present perfect, we can define a period of time before now by considering its duration, with for + a period of time, or by considering its starting point , with since + a point in time . FOR and SINCE can also both be used with the past perfect. SINCE can only be used with perfect tenses. FOR can also be used with the simple past. FOR + A PERIOD OF TIME for six years, for a week, for a month, for hours, for two hours I have worked here for five years. SINCE + A POINT IN TIME since this morning, since last week, since yesterday since I was a child, since Wednesday, since 2 o'clock I have worked here since 1990. PRESENT PERFECT WITH FOR She has lived here for twenty years. We have taught at this school for a long time. Alice has been married for three months. They have been at the hotel for a week. PRESENT PERFECT WITH SINCE She has lived here since 1980.