There is         sugar in my coffee. It's too sweet.

麦芽糖最早产生于（   ）

阅读下面的古诗，完成后面问题。
                                                                                                       十五夜望月
                                                                                                       （唐）王建
                                                                                       中庭地白树栖鸦，冷露无声湿桂花。
                                                                                       今夜月明人尽望，不知秋思落谁家？