It's the same gesture he makes when he comes home after a long day, turns off the key in his car and says, "Aah, I'm home." Because we all know where home is.
这与他回到家的时候做的是同样的姿势。 经过一天辛苦的工作，他拧钥匙熄灭了他的车，说， “啊，我到家了。”因为我们都知道家是哪。