我和他有相似的症状，但并不严重。

I've got the same symptoms, but not as bad.

youdao

她有点头痛，但并不严重。

She has a headache, but is not serious.

youdao

原油泄漏在北海发生的频率为大约一周一次，但大多数并不严重。

Oil spills occur in the North Sea at the rate of about one a week, but most are not serious.

youdao

And it turned out that another, not quite as deadly, but still very serious disease called syphilis was also common in this part of the world at that time.

现在已知另外一种疾病,它并不完全致命但也很严重,它叫梅毒,在那时的一些地方也很常见

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