在木材横切面上所见一个生长期内的木材和树皮生长层叫做（）。
A、横切面
B、生长轮
C、管孔
D、散孔材
参考答案：B
Mary is said _____ in the supermarket for 5 years, but I don’t know why she resigned last month.
A．to have been working
B．work
C．to be working
D．to have worked
彩红外与真彩色摄影应在色温（）范围内进行
A.4500~6800K
B.3500~4500K
C.6800~9200K
D.9200~10400K
