They become sticky and harden into the shape of the letter c, like a sickle, a hand tool with a curved blade.

红血球会变得粘稠，并且硬化成字母c的形状，像一种有弯曲刀片的手持工具，镰刀。

youdao

Hussein then FBI agent said he was suffering from AIDS, with a blade and cut his finger, so that he can leave blood stains in the letter.

候塞因随后对联邦调查局特工称，他患有艾滋病，他用刀片割破手指，这样他就可以在信件上留下血迹。

youdao

They become sticky and harden into the shape of the letter C, like a sickle, a hand tool with a curved blade.

VOA: special.2009.12.16