a great many 是形容可数名词还是不可数名词?

a.许多(很多,大量)1.A great many people think they are thinking when they are merely rearranging their prejudice.许多人,当他们正在整理自己的偏见之时,以为是在思考呢.dict.cn 2.Helen has a great many friends indeed,but she does not think she has any she can confide in.海伦固然有许多朋友,可是她认为没有一个是可以谈贴心话的.dict.cn 3.The city was even equipped with a drainage system,for a great many clay pipes were found beneath the narrow streets.这座城市甚至还敷设过排水系统,因为在窄窄的街道底下发现了许多陶土制的管道.

可数