The correct prepositions that complete the sentences in the...

Text 2:

Bad teaching habits: too much TTT

No teacher is perfect and all teachers have bad habits. Being a good teacher means reflecting (1) the following habits and trying to reduce them as much as possible. 

TTT stands (2) teacher talking time. Obviously, during the course of the class, it is necessary for the teacher to explain rules, give advice and talk about instructions, among other things. However, teachers should attempt to limit the amount of time that they spend speaking to the class in order to maximize the opportunity that the students have to speak. A good rule (3) thumb is aiming for around 30% of teacher talk to 70% of student talk. This means planning out what you will say, when and how.

Adapted from: www.bbc.co.uk/learningenglish