The teacher's comments are that he often speaks out about other people's faults, he speaks too directly to others, it's unpleasant and he's stubborn, he needs time to adjust to new things.
The teacher's comment is that he often says that others are not right. He speaks too directly to others, which is unpleasant and stubborn. He needs time to adapt to new things.
The teacher's comment is that he often criticizes others. He speaks to others too directly, which makes people unhappy and stubborn. He needs time to adapt to new things.