I recognise something has happened/I recognised that something has happened.

[Laladummy]

If I would like to tell somebody I discovered/ noticed something in email context, should I use simple present tense or simple past tense?
The event/things should have happened already and seems logically should use past tense.

1. I recognise something has happened
2. I recognised that something has happened

Which one is correct?

And under which occasions, simple present tense should be use and when to use simple past tense?

 

[5jj]

It's the normal use of the tenses. 'Recognise' denotes the present/ongoing state, 'recognised' the past moment of recognition.

 

[emsr2d2]

If I would like to tell somebody by email that I discovered/noticed something, in email context, should I use the simple present tense or the simple past tense?
The events/things should have happened already and so it seems logically logical that I should use past tense.

1. I recognise something has happened.
2. I recognised that something has happened.

Which one is correct?

And Also, under which occasions, in what circumstances/contexts should the simple present tense and the simple past should be used? and when to use simple past tense?