It will happen, as sure as a gun.

那是必定要发生的。

《新英汉大辞典》

Some of life behavior, although from the thing itself but as sure as a gun, look like, often is not possible.

人生有些行为，虽然千真万确，但从事情本身看，往往象是不可能的。

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However, needless to say, the wedding of friends sincere greetings and hope is as sure as a gun, although some still in want of perfection.

但是，毋庸讳言，婚礼中朋友们真诚的祝福和希望却是千真万确的，尽管还有些美中不足。

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