Hello teacher! I have a doubt! In what situation should i use “request” and “required”? Thanks.
I wish I had time to address this question more thoroughly but I don’t so I have erased my earlier partial answer. Have a great day and best wishes to all (including me)! 
@robertabalbino
I don’t think that you have a ‘doubt’. I imagine that you are interested in the difference between the two words, ‘request’ and ‘required’ and wanted to ask a ‘question’ about it.
@Yutaka Clearly Roberta has a doubt about the two words. It’s just much more common to say, “I have a question.”
But anyway, one way to look at it is that a “request” is something you ask for and a “requirement” is something you demand. The college requires you to maintain a 2.50 grade point average to keep your scholarship. The student requests a different date to take the exam.
Doubt says you are uncertain (meaning you do not know if you know). This is not very negative.
It can also mean that you “fear” that you do not know something which is slightly negative.
@ROBERTABALBINO
Use request when you ask for something.
Use required when an authority demands something.
An authority can be a parent, teacher, school, institution, government and more.
Thanks for the responses. I started studying English for 3 months, so I still write so badly. I still have many difficulties with simple things.
Thank you for your attention.
Roberta, I hope I can speak / write like you in three months from now in German. I think you are doing well.
No doubt, you are doing well.
When you are uncertain about a word, you can write here “I have a question about …” or you can look it up on Google yourself.
Good luck!