十亿零五十万零二十八写作____,它是一个____位数,最高位的计数单位是____.
People in Japan are supposed ____ (bow) when they meet for the first time.
What time does Ann ______ every day?
做好景区规划可以避免( )
①品牌之争 ②重复开发 ③低水平开发 ④盲目开发
请根据官能团的不同对下列有机物进行分类.
(1)芳香烃: ____ ; (2)卤代烃: ____ ;
(3)醇: ____ ; (4)酚: ____ ;
(5)醛: ____ ; (6)酮: ____;
(7)羧酸: ____; (8)酯: ____