sniffing

例句：

1. 1.The dog was sniffing the grass for a treat.
   狗在嗅探草地上的食物。
2. 2.The cat is always sniffing around in the trash can.
   猫总是在垃圾桶周围嗅来嗅去。
3. 3.She sniffed the air for any sign of danger.
   她嗅了嗅空气，寻找任何危险的迹象。