Отметьте правильно составленное предложение: 1. My sister, who is twenty years old, is a student. My sister, which is twenty years old, is a student. 2. He worked hard this month. He has worked hard this month. 3. What a nice man! What nice man! 4. Are there some chairs in the room? Are there any chairs in the room? 5. They walked faster. They walked more fast.