If people do not know how much they are eating, it can be really hard for them to stick to a diet.

如果人们不知道自己吃了多少，他们就很难坚持节食。

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She finds it impossible to stick to a diet.

饮食老受限制，她觉得受不了。

《牛津词典》

It's hard to stick to a diet that restricts such a big chunk of the food pyramid.

长期节食，严格限制食物金字塔中基础食物的摄入，困难。

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But for the time being, they's better stick to a diet that controls cholesterol.

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Most people can stick to a diet for awhile.

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To keep the disease under control he now takes tablets daily and has to stick to a special diet.

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