At a fantastic speed Fantastic是什么意思?

At a fantastic speed Fantastic是什么意思? the men scrambled back into the car and it moved off at a fantastic speedit moved off at a fantastic speed 这里的介词为什么是用at呢 为什么不是用in呢改成it moved off in a fantastic speed 不对吗能具体帮我分析下in 和at的 ar top speed为什么不说at a top speed with a high speed 还是at a high speed?China has developed -- such a high speed. the train passed at a terrific speed I'm having a fantastic time here at the 速度快是at a high speed 还是at the high speed at high speed 还是at a high speed,教材上是前一种两者区别是什么? at the speed of 和at a speed of的不同RT! at high/fast speedat high speed or at fast speed,要不要加a spread at a fast speed?介词用什么?at? at speed 还是at a speedNCE3 LESSON 25 at tremendous speed 用法没错吧 但为什么at a speed也对?区别在哪里呢 The train traves at a speed of 80 kilometres per hour 向划线部分(at a speed向at a speed of 80 kilometres per hour 提问 翻译 The speed limit is the fastest speed you are allowed to drive a car at. speed不是不可数嘛,那么at a high speed 又怎么说呢、、、 a speed the industry in our country has developed at ____ since 1979a. rapid speed b.quick speed c.high speed d. fast speed The car was going at a s_______ speed.