EuniceMonkey 小猴子的秘密花園～

現在完成式 present perfect 

表示一個 [ 經驗 ] 或是 時間不太確定, 時間不重要等. 

have / has + PP (V3)   ( Since , already , ever, never, so far, lately, recendly, ...... )

ex: I have already booked the hotel.（我已經定了飯店了

In present perfect , After Since , with simpel past （在現在完成式,如使用Since , Since後面使用簡單過去式）

ex: I have worn (V3) glasses since I was (simple past )  13 years old.

you also can use  " Sine "  or  " For "

ex: I have worn glasses since I was  13 years old.

or ex: I have worn glasses for 10 years.