What is a quality blog comment?

This activity was about kind quality blog comment. I was learning to put positive comment on blog post and my class too. We have to give kind quality blog comments in our Chromebook but some people can give bad comments in there Chromebooks. I look in Chromebook comments it's bad comments or good comments but our teacher say give good comments on Chromebooks and some give bad comments too we have to give good comments in Chromebooks.