Did you report your (loss) to the police?
The (lose) dog came back home itself last night.(这里应该是迷路的狗)
他们3个词组的区别在于:
loss是名词：损失, 遗失, 失败, 输, 浪费, 错过
lose是动词；遗失, 浪费, 错过, 输去, 使失去, 使迷路, 使沉溺于
lost是形容词：失去的, 丧失的, 错过的, 迷惑的, 不为人知的；
同时也是lose的过去式.