True, but not pure oxygen.

没错，但是那不是纯氧。

Pure oxygen is given to patients in certain circumstances.

某些情况下给病人吸纯氧。

Pure oxygen must be given patients in certain circumstances.

在某些情况下必须给病人吸纯氧。

In the new system, the coal is burned in pure oxygen instead of air.

在新系统中，煤炭在纯氧而不是空气中燃烧。

This item has been cleaned for a special service such as pure oxygen.

该产品已经清洗可用于如纯氧的特殊场合。