As a English non-native speaker it is difficult for me to understand when I must use present perfect or past simple because in my official language there isn't the present perfect tense.
I know that present perfect is related to something that happened in the past but its result is important now. But for instance:
- The message has been sent.
- The message was sent.
Please help me point me out any examples/contexts where I should use 1. instead of 2.