text: Energy keep you awake. Being concentrate shows interest on what you doing and comprehension is how much you understand. If you're sleepy you cannot do any of that. However, I want to focus more in the comprehension part. Never ever compare a teacher vs a computer. For example, you didn't understand the new unit because is confusing, you can always put your hand up and ask the teacher. The teacher will explain at their best for you to comprehend. On the contrary, you can't do it because you're at home and nobody can explain the material you don't understand.