report； leaf； wise； polite；   meaning

71．Don't be sad for the falling　　．They will come out next year．

72．Teenagers shouldn't just watch　　soap operas．

73．It's　　to enter a person's room without knocking at the door first．

74．Children should be taught how to spend their pocket money　　．

75．It was　　that China put its first homemade aircraft carrier in the water in Dalian on April 26，2017．