PRESENT PERFECT vs SIMPLE PAST.

1) Use (from Englishpage.com)

Present Perfect	Simple Past
Result of an action in the past is important in the present	action finished in the past
Recently completed actions	series of completed actions in the past
Actions beginning in the past and still continuing	together with the Past Progressive/Continuous - The Simple Past interrupted an action which was in progress in the past.
together with lately, recently, yet

2) Signal words

Present Perfect	Simple Past
just, yet, never, already, ever, so far, up to now, recently, since, for	yesterday, last week, a month ago, in 2002

3) Form

Present Perfect	Simple Past
have/has + past participle	regular verbs: infinitive + ed irregular verbs: 2nd column of the table of the irregular verbs

4) Examples

Present Perfect	Simple Past
4-1 Affirmative sentences
I have played football. I've played football.	I played football.
You have played football. You've played football.	You played football.
He has played football. He's played football.	He played football.

Present Perfect	Simple Past
4-2 Negative sentences
I have not played football. I've not played football. I haven't played football.	I did not play football. I didn't play football.
You have not played football. You've not played football. You haven't played football.	You did not play football. You didn't play football.
He has not played football. He's not played football. He hasn't played football.	He did not play football. He didn't play football.

Present Perfect	Simple Past
4-3 Questions
Have I played football?	Did I play football?
Have you played football?	Did you play football?
Has he played football?	Did he play football?

5) Spelling (both tenses)

stopped (Double the consonant after a short vowel.)

loved (one -e at the end of the word -> Leave out the -e and add -d.)

worried (consonant before -y ->Change to -ie.)  EXERCISE ONE EXERCISE TWO EXERCISE THREE