The bats probably also use magnetic fields and smell when they need, but it appears that for their regular nighttime excursions they depend most heavily on their memorized map.这句话中请问哪里有语法错误呢?谢谢回答
While
historically, the speed at which information moved was slower
than current times, firms still valued customer loyalty.请教各位老师,while historically, 这是分句一个省略句吗?