V. Choose the correct preposition. 1. Paul reads the newspaper by/at the beginning of the day. 2. She started her career at/in teaching when she was twenty three year sold. . 3. The teacher left Elliot in/at charge of the class while she was in the headmaster's office 4. Everyone congratulated him in/at the end of his lecture. 5. There are very few people who can work well under/on pressure.