Vi.
43. It is fun to go swimming on sunny day.
44. Peter is not old enough to watch that film.
45. It was not until the electricity was cut off that they paid the bill.
46. She left the room without saying a word.
47. Laura last saw her brother when he left for Japan. 
48. By the time we got to the cinema, the film had started.
49. It was not until the war ended that he returned to his native village. 
50. She has worked as an actress for ten years.