What are the teachers missing after the schools reopened?

Read the given passage and answer the questions that follow.

In the three days since schools reopened for junior students after two years, teachers are missing the familiar buzz in classrooms and have found a section of students to be unusually quiet. Some students are ‘withdrawn’, their social skills having been impacted by the long closure of schools. Teachers and counsellors are hopeful this would pass soon and till then they would have to be patient with the children and keep a close eye on their behaviour. “Children might have developed behavioural problems such as screen addiction and restlessness. They might have become impulsive and are not attentive to lessons. Teachers have to be proactive about the mental health of the child,” said the psychiatrist.