How does a good teacher give feedback to the students?

By evaluating the amounts of work they have done, and weighing it next to what is expected from them in order to be able to explain to them what progress they have made and how they can improve themselves on a particular point.
Having done that, the teacher can also use non-direct ways of making sure the students are learning new things, such as letting the students present a certain skill or explain a certain lesson, and in that way it's like he's telling them what they understand or not through letting them tell him ....

By telling the students their strengths, praising their achievements and acknowledge their good traits and behaviors then followed by telling their areas for improvement that is for me a good feed backing.

by asking questions and helping students to correct their errors