Verbs

Present perfect vs. past simple

The present perfect is used to talk about:

-situations which started in the past and continue now.

• I have lived in Japan for 13 years.
• She has worked as a teacher for two months.

-experiences at an indefinite time in the past.

• I've been to Rome, but I've never been to Venice.
• Have you seen the new Woody Allen film?

When the situation is finished, we use the past simple.

• I have collected thousands of stamps. = I collect stamps now.
• I collected stamps when I was a child. = I don't collect stamps any more.
  NOT: I have collected stamps when I was a child.

When we are speaking about a completed experience at a specific time, we use the past simple. Compare these sentences:

• I've read Gone with the Wind. (when is not specified)
• I read Gone with the Wind when I was 15. (when is specified)
  NOT: I've read Gone with the Wind when I was 15.

The present perfect is used with expressions of unfinished time. Unfinished time started in the past and continues into the present.

The past simple is used with finished time; when there is no possibility of something happening again in that time period.

• I have already received 20 emails this morning and it’s only 10:30 a.m.! = unfinished time
• My parents moved to the UK in the 1970s. = finished time

Note:

Sometimes an expression that usually refers to unfinished time can be used with the past simple tense.

For example:

I received 40 emails this morning! Luckily, I have only received three this afternoon.

The speaker is talking in the afternoon so, for her, this morning is finished time.