母亲在给宝宝喂奶前先给奶瓶消毒。

The mother is ___sterilising the baby bottle before feeding.

兽医建议给猫咪做绝育手术以避免意外怀孕。

The vet recommended ___sterilising the cat to prevent unwanted pregnancies.

过度使用化肥正在使这片土地变得贫瘠，无法种植作物。

Excessive use of chemical fertilizers is ___sterilising the soil, making it impossible to grow crops.