Answer:
The words or phrases are challenging, exhaustive note taking and time-consuming lab work.
Explanation:
A demanding teacher is someone who requires from others more time, effort and attention than someone who doesn't expect much from the students. Therefore, in Professor Ramirez's classes, students will have to study very hard and take down notes without disregarding anything, making them really challenging. They have to pay a lot of attention and do a lot of lab work, a task that Professor Ramiraz evidently places emphasis on.
Challenging, exhaustive and time-consuming are the words that support Professor Ramirez is a demanding teacher.
Challenging means very difficult beyond your posibilities.
Exhaustive means including all possibilities, complete.
Time-consuming means something taking a lot of time.
