1、im- "not, opposite of" => "这里引申为：free from, exempt from" + mun- + -ize.
2、字面含义：free from or exempt from public service or duty, exempt from service or obligation. 也就是不用做公共服务，免除了公共服务。
3、按咱们古代的说法：就是不用服劳役。由此引申为：豁免、免除、免疫。

1. This gas mask can immunize you against poison gas.

防毒面具能使你免遭毒气袭击.

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2. Drinking regularly can improve physical quality and enhance ability to immunize.

经常饮用牛奶能提高人的身体素质,增强人体的免疫能力.

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3. After testing, this vaccine could be used to immunize individuals at high risk for SARS exposure.

经过测试, 这种疫苗可用来免疫与SARS病毒接触的高危人群.

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4. Using highly pure C - reactive protein ( CRP ) to immunize rabbits, a high titer anti - CRP anti - serum was obtained.

采用高纯度的C反应蛋白 ( crp ) 免疫兔, 获取高效价的 crp 抗体.

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5. To immunize people against H 5 N 1, two injections of the vaccine approximately one month apart are needed.

为获得对H5N1的免疫力,大约一个月需要分别注射该疫苗两次.

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