Alternating drills that emphasize heavy usage of the throwing arm with those that are less stressful provides some protection against excessive wear and tear.
交替练习，需要使用投掷臂的练习与那些压力较小的练习交替，提供了一些保护，防止过度磨损和撕裂。
2
Obama operatives in the Congress have already introduced 10 bills, if passed, will strip Americans of their 2nd Amendment rights to bare and arm weapons for security, protection, and defense.
In order to restrict the rising rate of fault current caused by short circuit on one arm of bridge of inverter, a kind of device named current loop protection circuit can be adopted.