 We can also use the present perfect tense to talk about:  1 a past action with a result in the present She isn’t here, but she ___________her mobile.

 We can also use the present perfect tense to talk about:  1 a past action with a result in the present She isn’t here, but she hasn’t taken her mobile.

 We can also use the present perfect tense to talk about:  1 a past action with a result in the present She isn’t here, but she hasn’t taken her mobile.  2 an activity that started in the past and continues into present __________here for half an hour.

 We can also use the present perfect tense to talk about:  1 a past action with a result in the present She isn’t here, but she hasn’t taken her mobile.  2 an activity that started in the past and continues into present I’ve been here for half an hour.

PRESENT PERFECT Emma has packed her case. (So her things are in the case now.) Mike has repaired the chair. (So it’s all right now.) The plane has just landed. I’ve turned the heating on. (It’s on now.) I’ve dropped my mobile. (It’s on the floor now.) PAST SIMPLE Emma packed her case last night. (Her things may be unpacked now.) Mike repaired the chair. (It may be broken again now.) The plane landed ten minutes ago. I turned the heating on earlier, but it’s off again now. I dropped my mobile, but it seems to be OK.

Say what you have/haven’t done so far/ up to now  I haven’t seen Helen since Monday.

Since is used for:  start of the time  a particular time Since Monday Present Past Monday start of the time

Say what you have/haven’t done so far/ up to now  She hasn’t written to me for four days

For is used for:  a period of time  a duration of time For four days Present Past

I have had this book _______ March 1 st. I have had this book _______ two weeks. I have been in Buffalo _______ I have been in Buffalo _______ half a year. I have known him _______ a month ago. I have known him _______ a month.