我国时代精神的核心是( )。
A．爱国主义
B．为人民服务
C．与时俱进
D．改革创新
参考答案：D
___ comfortably in his armchair, the old man enjoyed the light music over the radio with his eyes half ___ .
A．Seating ; closed
B．Seated ; closed
C．Sitting ; close
D．Sat ; closing
做20个棱长为30厘米的小正方体纸箱，至少需要多少平方米硬纸？
