The number one reason is cost.

头号原因是成本。

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Lack of water is the number one reason for day time fatigue.

缺水其实是白天容易疲劳的最大原因。

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The number one reason behind wrinkles is sun, avoid sunlight or use sunscreen lotion.

出现皱纹的最大原因在于阳光，避免阳光或用防晒霜。

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Now the number one reason, and we have to acknowledge it up front, is usually economically there's no alternative or people believe there's no alternative.

首要原因，我们必须承认，通常是因为，经济上没有其他选择,或者人们认为别无选择。

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Remember too that the number one reason why start-ups fail is for lack of capital.

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But the number one reason canning is better than bottling is taste, according to Simpson.

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The number one reason consumers will subscribe for email updates is to get special offers and promotional codes.

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