Tenses: present perfect simple and present perfect continuous

PRESENT PERFECT SIMPLE and PRESENT PERFECT CONTINUOUS

Form:

Present Perfect Simple	Present Perfect Progressive
irregular verbs: form of 'have' + 3rd column of irregular verbs Example: I / you / we / they have spoken he / she / it has spoken regular verbs: form of 'have' + infinitive + ed Example: I / you / we / they have worked he / she / it has worked	form of 'have' + been + verb + ing   Example: I / you / we / they have been speaking he / she / it has been speaking
Exceptions
Exceptions when adding 'ed' : when the final letter is e, only add d Example: love - loved after a short, stressed vowel, the final consonant is doubled Example: admit - admitted final l is always doubled in British English (not in American English) Example: travel - travelled after a consonant, final y becomes i (but: not after a vowel) Example: worry - worried but: play - played	Exceptions when adding 'ing' : silent e is dropped. (but: does not apply for -ee) Example: come - coming aber: agree - agreeing after a short, stressed vowel, the final consonant is doubled Example: sit - sitting after a vowel, the final consonant l is doubled in British English (but not in American English). Example: travel - travelling final ie becomes y. Example: lie - lying

USE:

Both tenses are used to express that an action began in the past and is still going on or has just finished. In many cases, both forms are correct, but there is often a difference in meaning: We use the Present Perfect Simple mainly to express that an action is completed or to emphasise the result. We use the Present Perfect Progressive to emphasise the duration or continuous course of an action.

Present Perfect Simple	Present Perfect Progressive
Result (what / how much / how often) I have written 5 letters. / I have been to London twice.	Duration (how long) I have been writing for an hour.

Present Perfect Simple	Present Perfect Progressive
Emphasis on completion I have done my homework. (Meaning: My homework is completed now.)	Emphasis on duration I have been doing my homework. (Meaning: That's how I have spent my time. It does not matter whether the homework is completed now.)

Present Perfect Simple	Present Perfect Progressive
desired result I have washed the car. (Result: The car is clean now.)	unwanted side effect Why are you so wet? - I have been washing the car. (side effect: I became wet when I was washing the car. It does not matter whether the car is clean now.)

Present Perfect Simple	Present Perfect Progressive
since the last time I haven't played that game for years. (Meaning: It's years ago that I last played that game.)	since the beginning I haven't been playing that game for an hour, only for 10 minutes. (Meaning: It's not even an hour ago that I started to play that game.)

Present Perfect Simple	Present Perfect Progressive
permanent James has lived in this town for 10 years. (Meaning: He is a permanent resident of this town.)	temporary James has been living here for a year. (Meaning: This situation is only temporary. Maybe he is an exchange student and only here for one or two years.)

Exercises:

http://www.ego4u.com/en/cram-up/grammar/prepersim-preperpro/exercises

http://www.ego4u.com/en/cram-up/grammar/prepersim-preperpro/exercises?ex03

http://www.ego4u.com/en/cram-up/grammar/prepersim-preperpro/exercises?ex04

http://www.ego4u.com/en/cram-up/grammar/prepersim-preperpro/exercises?ex06

http://www.ego4u.com/en/cram-up/grammar/prepersim-preperpro/exercises?ex08

http://www.ego4u.com/en/cram-up/grammar/prepersim-preperpro/exercises?ex10

http://www.ego4u.com/en/cram-up/grammar/prepersim-preperpro/tests?test1