Here’s the rewritten version of the sentences:

61. He said, “I will study hard for this entrance test.”
He said that he would study hard for that entrance test.

62. “Henry hates going to the beach at noon,” said George.
George said that Henry hated going to the beach at noon.

63. I said to my mother, “I have eaten the cake.”
I told my mother that I had eaten the cake.

64. I said to him, “Don’t you know the way home?”
I asked him if he didn't know the way home.

65. Ronnie asked us, “Are you leaving tomorrow?”
Ronnie asked us if we were leaving the next day.

66. Mrs. Hoa said, “This is our new apartment.”
Mrs. Hoa said that this was their new apartment.

67. The weatherman said, “It may rain tomorrow evening.”
The weatherman said that it might rain the next evening.

68. Joe said, “I came up with a great idea last night.”
Joe said that he had come up with a great idea the night before.

69. Christopher asked me, “Do you want to try this drink?”
Christopher asked me if I wanted to try that drink.

70. The students said, “We finished this essay two hours ago.”
The students said that they had finished that essay two hours earlier.