morning前的介词 warm

介词on: 构成on a warm morning

在一个温暖的早晨

On a warm morning， loud cheers erupted sporadically from the crowd of elderly men and women who had their eyes glued on an array of half a dozen television screens.

在一个温暖的早晨，喧嚣声不断地从一群老年男女中发出，他们的眼睛，死死的注视着眼前的六台一排的显示器。

应该用on表示在“某一时候”，如：on a warm morningon the morning of July 4th on a cold day