Go to your local library and read every book in the History stacks and you will have learned significantly less than 1% of the complete answer to your question. Read every patent ever filed anywhere in the world and you will also have learned significantly less than 1% of the complete answer to your question. Read every work of Philosophy and Religion ever written anywhere in the world and you will also have learned significantly less than 1% of the complete answer to your question. Read every paper ever published in every Scientific and Mathematics journal anywhere in the world and you will also have learned significantly less than 1% of the complete answer to your question.
The complete answer to your question cannot be found anywhere, least of all this website.
What happens now can only be affected by what is happening now. The future cannot affect the past.
What happens now can only be affected by what is happening now. The future cannot affect the past.
Present is now - what is currently happening - and past is anything and everything that has happened (been and gone).
At this occasion is happening now. On this occasion happend in the past.
The present perfect progressive.
Uniformitarianism
Sadly, it is happening almost all around the world right now.
present because it is happening now
The present tense expresses something that is happening now whilst the past tense expresses something that has already happened.
The present tense expresses something that is happening now whilst the past tense expresses something that has already happened.
The cheetah is not extinct.
Showing real life positions happening right now or things that happen in the past.