As to why fu should be placed upside down there are three interpretations.

1、

The Chinese character fu means good fortune and happiness, and during Spring Festival virtually every family would paste it upside down on their doors in the hope that the word could bring blessings to their families.

中国汉字福意味着好运和幸福。每到春节，几乎每个家庭都会将福字倒贴在家里的门上，以希望这个字能给家人带来祝福。

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2、

Jiang replied, You are off limits wherever there is good fortune When the residents got word of Jiang's instruction, they wrote the character fu on paper and pasted it on the doors and windows of their houses to keep the Goddess of Poverty away.

姜子牙答道：有好运的地方你都禁止踏入。居民们听到姜子牙的指示，就在纸上写下福字贴在家里的窗户上以赶走穷神。

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3、

You can however, turn the Chinese character for luck ( fu) upside down to make "dao" ( which sounds like arrival) and put it on your door to bring in good fortune for the new year.

但你可以把中国的汉字福字倒贴在门上（听起来像是福到）这样就能在新年带来好运了

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4、

She gave an order that every family should hang "happiness" upside down on the door.

她偷偷下令全城的人都把自己家门上的福字倒过来。

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5、

People had to buy holiday items one after another; the little booths on the streets all were selling New Years pictures, Door Gods, Spring Festival couplets, words such as "luck" and the like.

人们纷纷购买年货，街上的小摊儿全是年画、门神、春联、福字什么的。

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6、

The character-longevity, it means a long and happy life, said it works with the Hi-longevity, the very auspicious festive theme.

福字通福寿，寓意幸福长寿，故作品称福寿喜同贺，非常吉祥喜庆的题材。

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7、

He followed past practice and had several large fu written and pasted on the front gates of the warehouse and the mansion.

他遵照传统，命人在库房和王府大门上贴了几个大大的福字。

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8、

He also asked the soldiers to paste fu on the doors of those who did not join in the crowd.

他还命令士兵将没有参与这件事的人家贴上福字。

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9、

The second heart is made of jade and has the Chinese character Fu.

第二颗心是刻有中国汉字福字的玉坠。

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10、

Put these two & quot ; fu & quot ; characters at a greater distance from each other.

把这两个福字贴的隔开一点.

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11、

Up close their teeth are yellow and rotting and lines crease their faces.

但走近了就会发现,她们的牙齿发黄,都被蛀坏了,脸上皱纹横生.

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12、

Camping with a group is fun.

大伙露营是趣味横生的事.

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13、

His clouded with anger.

他眉宇之间怒气横生.

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14、

This book is very humorous.

这本书谐趣横生.

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15、

People would have flashes of happy expression.

人们偶尔会妙语横生.

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16、

The interest is horizontal to living, universal easy.

趣味横生, 普及容易.

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17、

They are fond of fun and therefore witty.

他们喜欢玩笑,所以情趣横生.

辞典例句

18、

The application of nano-technology to paints and plating was introduced.

介绍了纳米技术在涂料和电镀中的应用.

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19、

Yes, I think there should be international regulations against sex for nanotechnology.

是的, 我想,应该有部国际法规来反对性成为纳米技术的一部分.

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20、

Famous poet Li Bai, once regarded her as one of the seven sages in Tang Dynasty.

著名诗人李白, 就把武则天列为唐朝“七圣”之一.

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