妈妈用沸水消毒奶瓶以杀死细菌。

Mother uses boiling water to ___sterilise baby bottles and kill bacteria.

农场主通常会给牲畜做绝育手术以防止过度繁殖。

Farmers usually ___sterilise their livestock to prevent overbreeding.

这种一成不变的教学方式会扼杀学生的求知欲。

This rigid teaching method will ___stifle students' curiosity.