Why has the writer used "could" in the first sentence and "can" in the second sentence?
"You could also place students in a small group of four or five. In each group, you can have at least one advanced student and at least one beginner."
Why has the writer used "can" in the first sentence and "could" in the second and third sentences:
"You can divide your students into groups by their English level. You could simply do beginner, intermediate or advanced based on your initial interaction with your students or the quality of their first few assignments. You could also test your students to get a more exact level, using a test."