FOR ve SINCE ile Present Perfect
'Present perfect' kullanarak bir zaman aralığının süresini, for + bir zaman aralığı ile, ya da başlangıç noktasını, since + zamanda bir nokta ile dikkate alarak şu andan önceki bir zaman aralığını tanımlamak için kullanabiliriz. FOR ve SINCE aynı zamanda 'past perfect' ile de kullanılabilir. SINCE sadece tanımlanmış geçmiş zaman kipleri ile kullanılabilir. FOR aynı zamanda 'simple past' ile de kullanılabilir.
For + bir zaman aralığı
for six years, for a week, for a month, for hours, for two hours
I have worked here for five years.
SINCE + zamanda bir nokta
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.
FOR ile Present perfect
She has lived here for twenty years.
We have taught at this school for a long time.
Alice has been married forthree months.
They have been at the hotel for a week.
SINCE ile Present perfect
She has lived here since 1980.
We have taught at this school since 1965.
Alice has been married since March 2nd.
They have been at the hotel since last Tuesday.