Past simple and present perfect
I'm confused.When i should use past simple and when present perfect?As far as i know i use simple i know when it was, or if it is fact. Present perfect show us result in present.
I remembered i need to go... or
I've remembered i need to go... on the one side it is just fact "i remembered", on the other it is result in present "now i must go..."

How to know when i must use simple, when perfect?

Question

Past simple and present perfect
I'm confused.When i should use past simple and when present perfect?As far as i know i use simple i know when it was, or if it is fact. Present perfect show us result in present.
I remembered i need to go...   or
I've remembered i need to go...  on the one side it is just fact "i remembered", on the other it is result in present "now i must go..."

How to know when i must use simple, when perfect?

Answer

it's pretty confusing... however, simple past and present perfect tenses both describe fact acts.

you may visit this site for further information:

http://web2.uvcs.uvic.ca/elc/studyzone/410/grammar/ppvpast.htm

:)

Answer

Past simple is used for talking about the past.  You also need to indicate when this event happened (ie. by giving a time, or putting the event in a sequence with other past events).  It has no connection to the present situation.

Present perfect is used for talking about now. You're using a past event which explains or refers to the current situation.

Answer

В вашем случае "I've remembered I need to go..." (я вспомнил, что я дожен был бы...) применяется не эта форма модального глагола как "must", а другая "had (to)" или "was (to)": (1) I remembered that I had to go there yesterday = Я вспомнил, что я должен был пойти туда. или (2) I remembered that I was to send him a letter, but I forgot = Я вспомнил, что я должен бы послать ему письмо, но я забыл.

Answer

You use Present Perfect to talk about an action which started in the past and continuous up to now, to talk about a past action that has the result in the present, ...Hmm, you can see the differences here: http://web2.uvcs.uvic.ca/elc/studyzone/410/grammar/ppvpast.htm ^^