1-نستخدم How long للسؤال عن طول المده مع المضارع التام
How long have Tom and Ann known each other?
كذلك مع المضارع التام المستمر
How long has it been raining?
اما الماضى البسيط نستخدم When
When did it start raining?
وكذلك How long ago
How long ago did it start raining?
2-لا نستخدم for فى التعبيرات التى بها all(all day- all morning.......etc)
I've lived here for my life.I have lived here all my life.
عند استخدام since
I have lived here since I was born.
3-لابد ان نقف امام هذا التعبير
How long is it since you had a holiday?
It's two years since I had a holiday.
عند استخدامfor
I haven't had a holiday for two years.
4- خلى بالك
George hasn't been feeling very well recently.
Have you been working hard today?
5-عجيب....................
It's ages since Tom visited us.
عند استخدام for
Tom hasn't visited us for ages.
6-Shakespeare wrote Hamlet. لانه مات اما اذا كان الكاتب على قيد الحياه نقول has written لانه ما زال يكتب
7-My father has always worked hard.
Tom has had a cold for the past week.
8- اذا وجدنا this morning
I have written two letters this morning. تكون مضارع تام اذا قيلت فى الصباح لان مازال الصباح فهى مضارع تام اما اذا قيلت بعد انتهاء الصباح فهى ماضى بسيط
I wrote two letters this morning .وقس على ذلك this afternoon-this evening