一、原因状语从句的引导词及用法

原因状语从句通常由 because、since、as、now that 等引导。

1. because 表示直接原因，语气最强，回答 why 的提问。

- I didnt go to school yesterday because I was ill.（我昨天没去上学是因为我生病了。）

- She is crying because she lost her favorite book.（她在哭是因为她丢了最喜欢的书。）

2. since 和 as 表示较为明显的原因，语气较弱，通常可互换。

- Since/As it is raining, wed better stay at home.（既然下雨了，我们最好待在家里。）

- As/Since you are not feeling well, you should go to see a doctor.（由于你感觉不舒服，你应该去看医生。）

3. now that 表示“既然”，通常用于现在的情况。

- Now that you have grown up, you should be more responsible.（既然你已经长大了，你应该更有责任感。）

二、例句

1. Because he was tired, he went to bed early.（因为他累了，所以他早早地上床睡觉了。）

2. She didnt come to the party because she had a lot of homework to do.（她没有来参加聚会是因为她有很多作业要做。）

3. Since it is Sunday, we can go for a picnic.（既然今天是星期天，我们可以去野餐。）

4. As it is getting dark, we should go home.（因为天渐渐黑了，我们应该回家了。）

5. Now that you have time, lets talk about it.（既然你有时间，我们来谈谈这件事吧。）

6. He failed the exam because he didnt study hard.（他考试不及格是因为他没有努力学习。）

7. She is angry because he broke her favorite vase.（她很生气是因为他打碎了她最喜欢的花瓶。）

8. Since you have promised, you should keep your word.（既然你已经承诺了，你就应该遵守诺言。）

9. As it is a fine day, we decided to go on a picnic.（因为天气很好，我们决定去野餐。）

10. Now that we have enough money, we can buy a new car.（既然我们有足够的钱了，我们可以买一辆新车。）

11. Because of the heavy rain, we had to stay at home.（因为大雨，我们不得不待在家里。）

12. She is late because of the traffic jam.（她迟到是因为交通堵塞。）

13. Since you are interested in music, you can join the music club.（既然你对音乐感兴趣，你可以加入音乐俱乐部。）

14. As it was very cold, we wore thick clothes.（因为天气很冷，我们穿了厚衣服。）

15. Now that you know the truth, you can make a decision.（既然你知道了真相，你可以做决定了。）

16. He cant go with us because he has to look after his sick mother.（他不能和我们一起去是因为他得照顾他生病的母亲。）

17. She is sad because her pet dog died.（她很伤心是因为她的宠物狗死了。）

18. Since it is your birthday, lets celebrate.（既然今天是你的生日，我们来庆祝一下吧。）

19. As you are so busy, I wont disturb you.（因为你这么忙，我就不打扰你了。）

20. Now that you have graduated, what are your plans?（既然你已经毕业了，你有什么计划？）

21. Because he is honest, everyone trusts him.（因为他很诚实，所以每个人都信任他。）

22. She is happy because she got a good grade in the exam.（她很高兴是因为她在考试中取得了好成绩。）

23. Since you have a car, you can drive us there.（既然你有车，你可以开车送我们去那里。）

24. As it is a holiday today, the shops are closed.（因为今天是假日，商店都关门了。）

25. Now that you are here, lets start the meeting.（既然你在这里，我们开始开会吧。）

26. He is tired because he worked all day.（他很累是因为他工作了一整天。）

27. She is worried because her son hasnt come back yet.（她很担心是因为她的儿子还没有回来。）

28. Since you are my friend, I can tell you my secret.（既然你是我的朋友，我可以告诉你我的秘密。）

29. As it is very hot, we want to go swimming.（因为天气很热，我们想去游泳。）

30. Now that you have learned English for many years, you should be able to speak it fluently.（既然你学英语已经很多年了，你应该能够流利地说英语了。）

31. Because he is kind-hearted, he often helps others.（因为他心地善良，他经常帮助别人。）

32. She is excited because she is going on a trip tomorrow.（她很兴奋是因为她明天要去旅行。）

33. Since you are good at math, you can help me with my homework.（既然你擅长数学，你可以帮我做家庭作业。）

34. As it is snowing, the ground is covered with white snow.（因为正在下雪，地面被白雪覆盖着。）

35. Now that you have understood the question, you can answer it.（既然你已经理解了这个问题，你可以回答它了。）

36. He is angry because she lied to him.（他很生气是因为她对他撒谎了。）

37. She is disappointed because she didnt win the game.（她很失望是因为她没有赢得比赛。）

38. Since you have time, you can read some books.（既然你有时间，你可以读一些书。）

39. As it is windy, we should close the windows.（因为风很大，我们应该关上窗户。）

40. Now that you have made a mistake, you should correct it.（既然你犯了一个错误，你应该改正它。）

41. Because he is lazy, he didnt finish his work on time.（因为他很懒，他没有按时完成工作。）

42. She is nervous because she is going to give a speech.（她很紧张是因为她要发表演讲。）

43. Since you are a student, you should study hard.（既然你是一名学生，你应该努力学习。）

44. As it is late, we should go to bed.（因为很晚了，我们应该睡觉了。）

45. Now that you have decided to do it, dont give up easily.（既然你已经决定做这件事了，就不要轻易放弃。）

46. He is sad because his friend is leaving.（他很伤心是因为他的朋友要走了。）

47. She is happy because she received a beautiful gift.（她很高兴是因为她收到了一份漂亮的礼物。）

48. Since you are in a hurry, I wont keep you.（既然你很匆忙，我就不耽误你了。）

49. As it is raining hard, we cant go out.（因为雨下得很大，我们不能出去。）

50. Now that you have grown up, you should take care of yourself.（既然你已经长大了，你应该照顾好自己。）

51. Because he is talented, he was chosen to join the team.（因为他很有才华，他被选中加入了这个团队。）

52. She is proud because her daughter won the first prize.（她很自豪是因为她的女儿获得了一等奖。）

53. Since you are free, why not come with us?（既然你有空，为什么不和我们一起去呢？）

54. As it is a beautiful place, many people come to visit.（因为这是一个美丽的地方，很多人来参观。）

55. Now that you have known the result, whats your opinion?（既然你已经知道了结果，你有什么看法？）

56. He is worried because he lost his wallet.（他很担心是因为他丢了钱包。）

57. She is angry because he didnt listen to her.（她很生气是因为他不听她的话。）

58. Since you are new here, let me introduce you to others.（既然你是新来的，让我把你介绍给其他人。）

59. As it is Sunday tomorrow, we can go shopping.（因为明天是星期天，我们可以去购物。）

60. Now that you have finished your work, you can have a rest.（既然你已经完成了工作，你可以休息一下了。）

61. Because he is brave, he is not afraid of difficulties.（因为他很勇敢，所以他不怕困难。）

62. She is excited because she is going to see her idol.（她很兴奋是因为她要去见她的偶像。）

63. Since you are interested in painting, you can join the art club.（既然你对绘画感兴趣，你可以加入艺术俱乐部。）

64. As it is a sunny day, we can go for a walk.（因为今天是晴天，我们可以去散步。）

65. Now that you have learned a lot, you can share your experience with others.（既然你已经学到了很多，你可以和别人分享你的经验。）

66. He is tired because he played basketball for a long time.（他很累是因为他打了很长时间的篮球。）

67. She is sad because her grandfather passed away.（她很伤心是因为她的爷爷去世了。）

68. Since you are good at cooking, you can make a delicious meal for us.（既然你擅长烹饪，你可以为我们做一顿美味的饭菜。）

69. As it is getting late, we should hurry up.（因为时间越来越晚了，我们应该快点。）

70. Now that you have understood the importance of time, you should make good use of it.（既然你已经理解了时间的重要性，你应该好好利用它。）

71. Because he is careful, he seldom makes mistakes.（因为他很细心，所以他很少犯错误。）

72. She is happy because she got a promotion.（她很高兴是因为她得到了晋升。）

73. Since you are busy, I will do it for you.（既然你很忙，我来为你做这件事。）

74. As it is a holiday, we can relax and have fun.（因为今天是假日，我们可以放松一下，玩得开心。）

75. Now that you have made a decision, stick to it.（既然你已经做出了决定，就要坚持下去。）

76. He is angry because she broke his promise.（他很生气是因为她违背了她的诺言。）

77. She is disappointed because she didnt pass the driving test.（她很失望是因为她没有通过驾驶考试。）

78. Since you have time, you can visit some museums.（既然你有时间，你可以参观一些博物馆。）

79. As it is a beautiful season, we can go on a picnic.（因为这是一个美丽的季节，我们可以去野餐。）

80. Now that you have graduated from college, what are your plans for the future?（既然你已经大学毕业了，你对未来有什么计划？）

81. Because he is generous, he often donates money to charity.（因为他很慷慨，所以他经常向慈善机构捐款。）

82. She is excited because she is going to a concert tonight.（她很兴奋是因为她今晚要去听音乐会。）

83. Since you are interested in history, you can read some historical books.（既然你对历史感兴趣，你可以读一些历史书籍。）

84. As it is a fine day, we can go fishing.（因为今天天气很好，我们可以去钓鱼。）

85. Now that you have learned a new language, you can communicate with more people.（既然你已经学会了一门新语言，你可以和更多的人交流。）

86. He is tired because he worked overtime yesterday.（他很累是因为他昨天加班了。）

87. She is sad because her best friend is moving away.（她很伤心是因为她最好的朋友要搬走了。）

88. Since you are good at singing, you can participate in the singing competition.（既然你擅长唱歌，你可以参加歌唱比赛。）

89. As it is getting cold, we should wear more clothes.（因为天气越来越冷了，我们应该多穿点衣服。）

90. Now that you have known the truth, you should forgive him.（既然你已经知道了真相，你应该原谅他。）

91. Because he is hardworking, he always gets good grades.（因为他很努力，所以他总是取得好成绩。）

92. She is happy because she received a letter from her pen pal.（她很高兴是因为她收到了她笔友的一封信。）

93. Since you are free this afternoon, lets go to the park.（既然你今天下午有空，我们去公园吧。）

94. As it is a rainy day, we can stay at home and watch movies.（因为今天是雨天，我们可以待在家里看电影。）

95. Now that you have grown taller, you can reach the top shelf.（既然你已经长高了，你可以够到顶层的架子了。）

96. He is angry because she interrupted him.（他很生气是因为她打断了他。）

97. She is disappointed because she didnt get the job she wanted.（她很失望是因为她没有得到她想要的工作。）

98. Since you have time, you can help me clean the room.（既然你有时间，你可以帮我打扫房间。）

99. As it is a beautiful night, we can go for a walk under the stars.（因为这是一个美丽的夜晚，我们可以在星空下散步。）

100. Now that you have learned to swim, you can go swimming in the sea.（既然你已经学会了游泳，你可以去海里游泳。）