Preview – Present Perfect vs simple past (BrE)

FORM:

The present perfect is formed with HAVE + Past Participle. The past participle is formed like the past tense, by adding -ED to the verb:

SIMPLE PAST: I worked in Salamanca for two years (work + ed = worked)
PRESENT PERFECT: I have worked in Salamanca for two years (have + worked)

You have talked to Ky - You haven't talked to Ky - Have you talked to Ky?

Irregular verbs use their third form:

write - wrote - written

   PRESENT:    I write an email to my girlfriend every day
   SIMPLE PAST:    I wrote a letter to my mother yesterday
   PRESENT PERFECT:    She has written a letter to Kyle this morning

Spelling note: Verbs ending in -e drop the -e (live + ed = lived), verbs ending in consonant + y change the Y into I (carry + ed = carried), verbs ending in a stressed vowel+consonant double the final consonant (tap + ed= tapped)

USAGE:

We need 2 conditions to use the present perfect

connection we use the present perfect to refer to actions when there is a connection between the past and the present (that's why we call it present perfect). The past tense refers to finished past actions with no connection with the present.

	Yesterday I went to the cinema		(that’s just something I did yesterday)
	I remember all the names because I have learned the list from memory		(I learned, so now I know)
	My father has given me a new phone		(now I have a new phone)
	Cassia has lived here for five years		(and she still lives here now)

when? we use the past tense when people can answer the question “when?”: the moment is said or already known and it is a past time. (we know when and it is a past when).

	I saw it last week	when?	Last week
	I saw it when I was at my sister’s	when?	when I was at my sister's
	She visited us in June	when?	in June

We can only use the present perfect when people can’t answer the question “when?” or if the answer is a present period of time.
	I have visited Paris and Rome	when?	I don’t know
	I’ve been to the park today	when?	Today: a present period of time
	She has loved him since she was a child	when?	since she was a child (until now, so present too)

Notice:
- I have visited Rome, and I stayed in a very nice hotel. We spent five days there.
1st verb: I have visited (I don't say when and you don't know)
2nd verb: I stayed... (when? when I visited Rome)
2nd sentence: We spent... (when? when I visited Rome)
So the first part of the sentence gives us a time reference that will be used for the second part or even other following sentences talking about my visit to Rome.

This is the standard British usage, in America you can also apply these rules but they often use the simple past in sentences where a British person will always use a present perfect, so do not be surprised to find examples like this:
I didn't go to school today I haven't gone to school today (when? today: a present period of time)
Look, I bought a new car Look, I have bought a new car (so now I have a new car)

For more advanced explanations about the use of the Present Perfect go to this article: Present Perfect: uses.

Equivalencias del PRESENT PERFECT en español

Normalmente se traduce por el pretérito perfecto:
- I have bought a book for you = te he comprado un libro

Pero si mencionamos un período de tiempo presente se suele traducir por el presente:
- I have lived here for five years = Vivo aquí desde hace dos años = llevo dos años viviendo aquí
- I have known Amy since I was a child = conozco a Amy desde que era pequeño

Hay veces que el español usa un pretérito perfecto cuando el inglés usa un simple past, recuerda las dos reglas de "connection" y "when?", que en español no se cumplen:
- I saw your father yesterday = ayer he visto a tu padre

Y por último, ten en cuenta que las reglas de uso del español en este caso pueden cambiar de una región o país a otro:
- No te oigo bien, ¿qué has dicho? (Castilla)
- No te oigo bien, ¿qué dijiste? (Canarias, etc)