I have learned about the academic language and that it has to be formal not informal, concise meaning not too long, have to follow logical structure and be cohesive and coherent.

Formality is used in a situations that  are very serious or involve people we don't know ( in written comments)

Informal is used in a situations that are not serious and and more related and involve people we know very well.

We answered with Yes or No to the photos that the lecture displayed on and ask questions.

We also did 3 class activities.