Because tofu is rich in calcium, vinegar will cause the calcium in tofu to be converted into substances that are difficult for the human body to digest. "Tofu mixed with vinegar" may be to increase the flavor of tofu, but it causes the human body to be unable to absorb the nutrients in tofu. Isn't this redundant and useless?

In addition, it is not advisable to mix tofu and shallots, which is common in daily life. Calcium in tofu will react with oxalic acid in shallots to form calcium oxalate, which is difficult for human body to absorb.

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Other idioms and proverbs that describe helping others.

Pull out the seedlings to help them grow, because they grow too slowly, and lift them up with your hands to help them grow. The metaphor ignores the objective law of the development of things and insists on quick success and instant benefit, which makes things worse.

Failure is failure, which means that you can't do things well, but make things worse.

To paint a snake to add feet is to add feet to the snake when painting it. It is not only useless but also inappropriate to do something superfluous. It is also a metaphor for fictional facts.

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