4 Choose the correct preposition. 1 Paul reads the newspaper at the beginning of the day. 2 She started her career in teaching when she was twenty-three years old. 3 The teacher left Elliot in charge of the class while she was in the headmaster’s office. 4 There are very few people who can work well under great pressure. 5 He left school at the age of sixteen. 6 Everyone congratulated him at the end of his lecture.