当房地产开发商将建成后的物业用于出租或______时，短期开发投资就转变成了长期置业投资。
A．出售 B．抵押 C．转让 D．经营
参考答案：D
He prefers _____ in doors ___out this afternoon. [ ]
A. to stay, to go
B. staying, to going
C. to stay, to go
D. staying, to go
什么是主体化机车信号？
