垂带石
参考答案：在垂带踏跺两旁，其中线与明间檐柱中线重合，尺寸同阶条石，清代不砌象眼。
(2013·天津12区二模)He never thought that his success came ________ he least wanted it.
A．until
B．since
C．when
D．while
可以用下图所示装置收集并干燥的气体是
A．H2
B．NH3
C．Cl2
D．SO2
