The Greens used to live in London and now they _________ in Beijing.
A:used to live
B:are used to live
C:are used to living
D:are used for living
已知点(2,5)和(8,3)是函数y=﹣k|x﹣a|+b与y=k|x﹣c|+d的图象仅有的两个交点,那么a+b+c+d的值为____
中国改变工业落后的面貌,开始向社会主义工业化迈进的标志性事件是( )