Daniel started to play_________ piano when he was________ 11-year-old boy.
A:/, a
B:the, a
C:a, a
D:the, an
— _____
— It is August 1st.
我国历来重视民族团结和注重对边疆的有效管理。下列汉唐时期的行政或军事机构管辖的地区是( )