I like reading 21st Century, but my teacher told me I’d better read more articles written by native authors. Do you think it’s a piece of good advice?
Of course, a great deal of 21st Century is written by native authors (like me, for example!), but I agree with your teacher that you should read as widely as you can. You don’t want to read pieces which are mainly about language and language learning, so try to read articles in general magazines (either local or international). Yes, your teacher has given you a good piece of advice.