So what I mean is that you can start a call in your house in the Wi-Fi hotspot, you can get in your car and talk until the battery's dead -- which would be like 10 minutes --  And the call will continue to be free.
我想说的是，如果你开始打电话的时候 是在你家里的无线热点里面的话 你可以坐上车一直打电话到你手机没电为止 也就10分钟左右吧  那个电话会继续免费