Let the teacher mention this, expose kindly the motive which leads to it, and tell them it is as irregular to answer before the rest as after them.
2.

Some will defer their answers until they can catch those of their comrades for a guide.

Let the teacher mention this fault, expose the motive which leads to it, and tell them that if they do not answer independently and at once, they had better not answer at all.
3.

Some will not answer at all.

The teacher can see by looking around the room who do not, for they can not counterfeit the proper motion of the lips with promptness and decision unless they know what the answer is to be.