Chuyển các câu với động từ chỉ nhận thức sau sang câu bị động

64. I have heard her sing this song several times.

65. People saw him steal your car.

66. The teacher is watching the work.

67. He won't let you do that silly thing again.

68. People don't make the children work hard.

69. They made him work all day.

70. The detective saw the woman putting the jewelry in her bag.

71. The terrorists made the hostages lie down.

72. Police advise drivers to use an alternative route.

73. She helps me to do all these difficult exercises.