C Complete the conversation with the sentences in the box. Write the main structures of the sentences in the blanks.
a The earth turns once every day. d That's a great question.
b Both halves always have different seasons. e It gets more direct sunlight.
c Our planet is so interesting. f It leans (倾斜) a little.
Mike: Dad, winter just started here in Hangzhou, but it's summer in Auckland. Why do different parts of the world have different seasons?
Dad: (1)
Mike: But why?
Dad: It's because of how the earth moves. (3)
Mike: I know that much.
Dad: But did you know that this imaginary pole isn't straight up and down? (4)
Mike: Yes, that's true. It's snowy too! So … when the northern half starts leaning towards the sun, we will have summer?
Dad: Exactly!
Mike: (6)
Dad: No problem, Mike.
a The earth turns once every day. d That's a great question.
b Both halves always have different seasons. e It gets more direct sunlight.
c Our planet is so interesting. f It leans (倾斜) a little.
Mike: Dad, winter just started here in Hangzhou, but it's summer in Auckland. Why do different parts of the world have different seasons?
Dad: (1)
d
Our earth is divided into the northern half and the southern half. (2) b
Mike: But why?
Dad: It's because of how the earth moves. (3)
a
It turns around an imaginary pole in its centre.Mike: I know that much.
Dad: But did you know that this imaginary pole isn't straight up and down? (4)
f
Right now, the southern half of the planet is leaning towards the sun. (5) e
That's why it's summer there. Up here, the northern half is leaning away from the sun. We don't get as much direct sunlight, so it's colder here.Mike: Yes, that's true. It's snowy too! So … when the northern half starts leaning towards the sun, we will have summer?
Dad: Exactly!
Mike: (6)
c
Thanks for explaining this to me, Dad.Dad: No problem, Mike.
答案：【解析】：
这是一道英语语法和句子结构填空的题目，同时要求写出句子主干结构。题目给出了一个对话，对话中父亲向Mike解释了为什么世界上不同地方有不同的季节。对话中有6个空白处需要填写，同时需要分析所填句子的主要结构。
1. 对于第一个空白处，需要填入一个引导解释或回答问题的句子。选项d "That's a great question." 是一个常用的回答，表示对问题的赞赏，并引出接下来的解释。
2. 第二个空白处需要描述地球被分为两半的情况。选项b "Both halves always have different seasons." 直接说明了地球两半的不同季节，与Mike的问题相呼应。
3. 第三个空白处需要描述地球的运动方式。选项a "The earth turns once every day." 准确地描述了地球每天自转一次的事实。
4. 第四个空白处需要解释地球自转轴倾斜的原因。选项f "It leans a little." 直接说明了地球自转轴是倾斜的。
5. 第五个空白处需要描述地球南半球倾向太阳时的季节情况。选项e "It gets more direct sunlight." 解释了为什么南半球是夏天，因为它得到了更多的直射阳光。
6. 第六个空白处是Mike对父亲解释的回应。选项c "Our planet is so interesting." 表达了Mike对地球现象的兴趣和好奇。
主干结构分析：
1. "That's a great question." 主干为 "That's a question."
2. "Both halves always have different seasons." 主干为 "Both halves have seasons."
3. "The earth turns once every day." 主干为 "The earth turns."
4. "It leans a little." 主干为 "It leans."
5. "It gets more direct sunlight." 主干为 "It gets sunlight."
6. "Our planet is so interesting." 主干为 "Our planet is interesting."
【答案】：
1. d (主干: That's a question.)
2. b (主干: Both halves have seasons.)
3. a (主干: The earth turns.)
4. f (主干: It leans.)
5. e (主干: It gets sunlight.)
6. c (主干: Our planet is interesting.)
这是一道英语语法和句子结构填空的题目，同时要求写出句子主干结构。题目给出了一个对话，对话中父亲向Mike解释了为什么世界上不同地方有不同的季节。对话中有6个空白处需要填写，同时需要分析所填句子的主要结构。
1. 对于第一个空白处，需要填入一个引导解释或回答问题的句子。选项d "That's a great question." 是一个常用的回答，表示对问题的赞赏，并引出接下来的解释。
2. 第二个空白处需要描述地球被分为两半的情况。选项b "Both halves always have different seasons." 直接说明了地球两半的不同季节，与Mike的问题相呼应。
3. 第三个空白处需要描述地球的运动方式。选项a "The earth turns once every day." 准确地描述了地球每天自转一次的事实。
4. 第四个空白处需要解释地球自转轴倾斜的原因。选项f "It leans a little." 直接说明了地球自转轴是倾斜的。
5. 第五个空白处需要描述地球南半球倾向太阳时的季节情况。选项e "It gets more direct sunlight." 解释了为什么南半球是夏天，因为它得到了更多的直射阳光。
6. 第六个空白处是Mike对父亲解释的回应。选项c "Our planet is so interesting." 表达了Mike对地球现象的兴趣和好奇。
主干结构分析：
1. "That's a great question." 主干为 "That's a question."
2. "Both halves always have different seasons." 主干为 "Both halves have seasons."
3. "The earth turns once every day." 主干为 "The earth turns."
4. "It leans a little." 主干为 "It leans."
5. "It gets more direct sunlight." 主干为 "It gets sunlight."
6. "Our planet is so interesting." 主干为 "Our planet is interesting."
【答案】：
1. d (主干: That's a question.)
2. b (主干: Both halves have seasons.)
3. a (主干: The earth turns.)
4. f (主干: It leans.)
5. e (主干: It gets sunlight.)
6. c (主干: Our planet is interesting.)