have/has + past participle
Example: He has finished his homework.
have/has not + past participle
Example: I haven't finished my homework.
have/has ... + past participle?
Example: Have you finished your homework?
The principal uses of the present perfect are listed below.
To refer to a time period which is not yet finished (e.g. today, this month):
We**'ve bought** a new house this week. (an incomplete period)
To show that something happened in the past. We don't state when is happened:
I**'ve lost** my watch. Have you seen it anywhere?Note: If we give the time we must use the simple past:
I lost my watch yesterday. (not I've lost my watch yesterday)The following time expressions are often used: ever, never, always, up to now, so far.
This is the worst storm we**'ve ever had**. (at any point before now)To talk about a situation which started in the past and usually continues after the time of speaking in the present:
He has lived here for six years. (He has lived here till now)
We use for with a lenght of time (e.g. for three weeks, for two days, for six years) and since with a point in time (e.g. since 2010, since Wednesday, since nine o'clock, since I was five, since I moved here)
To talk about an action which occured at an unstated time in the past, provided that there is still a connection with the present:
I**’ve collected** all the documents that are needed for the house sale. (I have the documents now)Note: If we give the time we must use the simple past:
I lost my watch yesterday. (not I've lost my watch yesterday)The following time expressions are often used: recently, just, already, and yet with negatives or questions.
I**'ve just arrived**.
Have you done your homework yet?
Compare the use of the present perfect with the past simple:
Present perfect
Past simple
links the past with the present:
John has won several awards. (at some point before now and he may win more awards)
only talks about the past:
John won several awards in 2012.
does not talk about a specific time in the past:
Have you read the latest issue of the Magazine? (at some time before now)
states a specific past time, or the time is understood:
I read the latest issue of the Magazine when I was at home. (I'm not at home now and the reading is finished)
uses time expressions that show the time period is unfinished:
I haven't seen John this morning. (up to 12 noon, the morning isn't finished)
uses time expressions that show the time is finished:
I didn't see John this morning. (after 12 noon, last morning has finished)
Note the position of the following time expressions that occur with the present perfect:
between the auxiliary and main verb (e.g. recently, already, always, ever, just, never):
I've already bought my ticket.
I’ve never met your brother.Ever is generally used with questions or negatives:
Have you ever been to London?after the main verb (e.g. all my life, every day, yet, before, for ages, for two weeks, since 2001, since I was ten etc.)
I haven't seen him for ages.
I’ve known John since I was ten.if there is an object clause, the time expression comes at the end:
I've read this book every morning since then.
He hasn't ridden since he broke his arm.