It's said ________ a little child does ________ much homework every day.
A:such; such
B:so; such
C:so; so
D:such; so
狒狒群中有首领,有分工.这是下列哪种行为的主要特征( )
一个做匀加速直线运动的质点,初速度是3m/s,加速度为4m/s2,求