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。
warm morning前的介词
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
