I overtook you at eight miles an hour这句话对吗

I overtook you at eight miles an hour这句话对吗 done,I,eight,when,miles,overtook,you,have,hour,an,you连词成句 "I was doing eighty miles an hour when I overtook you. "You needn't drive at seventy miles an hour. You must have been driving at seven miles an hour YOU MUST have been driving at seventy miles an hour.这里去掉AT可以 You must have been driving at seventy miles an/per hour. you must have been driving at seventy miles an hour为什么要用ing 英语翻译drive at 70 miles an hour.He is so fast.I coundn't bear 英语翻译60 miles an hour by new order i don't know if i told you 60 miles an hour The car ran at 100 miles an hour.中文意思,