Answer:
⦁ It is essential that the students should be encouraged to ask questions.
⦁ He was absorbed in thought and did not hear the doorbell.
⦁ We need to increase our awareness of environmental issues.
⦁ It is important that we should recycle as much as possible.
⦁ She is very talented and I am sure she will go far.
⦁ He was very pleased with himself and felt a sense of achievement.
Step-by-step explanation: