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
____
已知一个数是﹣2,另一个数比﹣2的相反数小3,则这两个数和的绝对值为____
下列物质中,由原子构成的是( )