下面哪项因素与固定桥基牙牙周潜力无关（）。 A.咀嚼肌纤维 B.牙槽骨 C.牙龈 D

幽默(humor)是生活中不可缺少的元素。请根据提示用英语写一篇短文，谈一谈幽默的重要性以及怎样培养幽默感。

The importance of humor	● win a lot of friends ● help solve problems ● ...
How to be humorous	● read some books which contain humorous stories ● …

注意: (1) 短文需包括上述全部要点,应适当增加细节, 以使行文连贯;
(2) 词数: 100左右, 短文开头已给出，不计入总词数。
Humor--- an important role in life 
One possible version:
Humor, as we know, is of great importance in our life.__________________________________
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