Since John met that girl he's gone weak in the head.

约翰自从遇见那姑娘之后，变得有些糊里糊涂了。

youdao

They also can interfere with mental ability, make muscles weak and cause pain in the head.

他们还可能干扰心理能力，使肌肉软弱，导致头部疼痛。

youdao

No sooner thought upon than done. There I lay on my elbows, in the most trying attitude, and every now and again gave a weak stroke or two to turn her head to shore.

说干就干，我支起胳膊时躺在那里，用最别扭的姿势不时轻轻划上一两桨，使船头转向岸边。

youdao

They also can become weak, expel material from the stomach, and suffer pain in the head or muscles.

VOA: special.2010.04.20

They also can interfere with mental ability,make muscles weak and cause pain in the head.

VOA: special.2010.07.27

And the muscles in their neck, that on Earth work all day to support the head, are weak, so they can easily sprain their neck by looking to the side, too quickly.

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