已知月球上物体受到的重力只有地球上的1/6，则一位航天员在地面上只能举起588N

—Jane, have you finished your paper?

—No, I ________ my sister with her drawing all the morning.

A．help

B．helped

C．was helping

D．have been helping

根据句意及首字母提示完成句子。

小题1:There are many people at the meeting, i________ me.

小题2:We must pay more attention to the s_________ of the players.

小题3:Don’t put off m_______ a travel plan before traveling.

小题4:During the past the three days, Jerry has visited many p________ of interest around Sydney.

小题5:Jack p_________ swimming to dancing and he is good at swimming.

当氮素不足时，即使二氧化碳浓度升高，植物的产出也不一定升高。

管理会计师对内部控制的贡献是增强组织资源安全管理的能力和信心。

在我国，为什么10kV系统一般不装设动作于跳闸的接地保护？