TheUnitedStatesisacountry_(advance)inscienceandtechnology
机枪每秒钟射出15颗子弹．每颗子弹质量为0.02kg，射出的速率为800m/s，则射击时的平均反冲力大小为（）
Theteacherrequiredthatallerrorsshouldbe_______eliminatedbeforethestudentsturnintheirtermpaper
thebossescannotdowithoutprofit,workershaveanedge.
Iwouldverymuch______tovisitsomeoftheplacesthatIhavebeenreadingabout.
