Past Simple or Present Perfect
I (be born) in Brazil
I was born in Brazil
They (live) in 5 countries so far.
They have lived in 5 countries so far.
I (love) chocolate since I was a child.
I have loved chocolate since I was a child.
They (go) home 20 minutes ago.
They went home 20 minutes ago.
Experiences
Present Perfect
I (work) in several companies before this.
I have worked in several companies before this.
He (not/do) the homework, teacher Debra!
He hasn't done the homework, teacher Debra!
I (study) so much this week I can barely sleep.
I have been studying so much this week I can barely sleep.
She (move) houses 3 times before she finally bought her own home.
She had moved houses 3 times before she finally bought her own home.
Facts, habits, routines in past.
Past Simple
I (graduate) in 2016.
I graduated in 2016.
They (not/meet) before that game last July.
They hadn't met before that game last July.
She (know) her best friend for more than 20 years.
She has known her best friend for more than 20 years.
We (arrive) in the classroom and then we (turn) on the lights.
We arrived in the classroom and then we turned on the lights.
Recent periods/durations in action verbs
Present Perfect Continuous
She (be) here many times.
She has been here many times.
She felt sick in the morning because she (eat) bad sushi the night before.
She felt sick in the morning because she had eaten bad sushi the night before.
He (clean) that window for 40 minutes now and it still looks dirty!
He has been cleaning that window for 40 minutes now and it still looks dirty!
Before last week, they (never/see) that movie.
Before last week, they had never seen that movie.
Experiences before past - "past of past"
Past Perfect
It (rain) so much lately.
It has rained so much lately.
They (study) hard before, so all of them passed the test with flying colours.
They had studied hard before, so all of them passed the test with flying colours.
It (rain) non-stop for two days now, we're all going to turn into frogs!
It has been raining non-stop for two days now, we're all going to turn into frogs!
He went home after he (finish) his test.
He went home after he had finished his test.
Used for feelings and states before now
Present Perfect