This is especially important for subway riders who frequently lose cell service while underground.

这对于地铁乘客来说尤为重要，这些人在地下时经常没有手机信号。

youdao

This is especially important for subway riders who frequently lose cell service while underground.

这对于地铁乘客来说尤为重要，这些人在地下时经常没有手机信号。

youdao