I live in the country and my father was a farmer.51. ______
He is now forty-five year old. Because of years of 52. ______
hard work, he looks old than his age. When I was53. ______
young, he is used to tell me the importance of study. 54. ______
Father knows little about English and other subjects, 55. ______
but he usually gives me some good advices on how56. ______
to learn my lessons good. He is not only kind to me 57. ______
but also very strict in me. With his help, I’ve made 58. ______
great progress. I’ll never to forget what he taught 59. ______
me. I think my father is best father in the world. 60. ______

汽轮机的工作过程就是把（）转变成（）。

A.热能，机械能

B.化学能，机械能

C.热能，电能

D.化学能，电能