SIMPLE PAST VS PRESENT PERFECTEnglish Grammar Online 4U, Simple Past – Present Perfect. http://www.ego4u.com/en/cram-up/grammar/simpas-preper, consulté le 03 mai 2009

Form

Simple Past tense Present Perfect tense

irregular verbs: Simple past of

irregular verbs, 2nd column.

Example:

I knew

Irregular verbs: form of 'have' +

past participle of irregular verbs,

3rd column

Example:

I / you / we / they have broken

he / she / it has broken

Regular verbs: infinitive + ed

Example:

I played

Regular verbs: form of 'have' +

infinitive + ed

Example:

I / you / we / they have played

he / she / it has played

Exceptions when adding 'ed':

1. When the final letter is e, only add d Example:love - loved

2, After a short, stressed vowel, the final consonant is doubled Example:

admit - admitted

3. After a consonant, final y becomes i (but: not after a vowel) Example:

worry - worriedbut: play - played

Use1. A time expression in the past is given, you have to use Simple Past

2. Certain time in the past or just / already / yet?

Simple Past tense Present Perfect tense

certain time in the past

Example:I called Mary 2 minutes ago.

just / already / not yet

Example:I have just called Mary.

3. Certain event in the past or how often so far? An action that took place / how often an action has happened till now.

Simple Past tense Present Perfect tense

certain event in the past

Example:

He went to Canada last summer.

whether / how often till now

Example:

Have you ever been to Canada? / I

have been to Canada twice.

4. Emphasis on action or result? Expressing what happened in the past with the result / putting the emphasis on the past action’s consequence in the present.

Simple Past tense Present Perfect tense

Emphasis on action

Example:

I bought a new bike. (just telling what

I did in the past.)

Emphasis on result

Example:

I have bought a new bike. (With

this sentence I actually want to

express that I have a new bike

now.)

Key Words to use properly with each tense

Simple Past tense Present Perfect tense

yesterday

... ago

in 1990

the other day

last ...

just

already

up to now

until now / till now

ever

(not) yet

so far

lately / recently

EXERCISE LINKS:

http://www.englishpage.com/verbpage/verbs5.htm

http://www.englishpage.com/verbpage/verbs6.htm

http://web2.uvcs.uvic.ca/elc/studyzone/410/grammar/ppvpast1.htm

http://www.better-english.com/grammar/pspp1.htm

http://www.english-zone.com/verbs/prsperf4.html

http://www.geocities.com/gob72/Simplevsperfectpast.htm

http://perso.wanadoo.es/autoEnglish/gr.perf.i.htm

http://a4esl.org/q/f/z/zz29bms.htm