13. net　 网， 净余的　　　 net weight 净重　 　　　net profit 净利润

12. nervous　 神经紧张的　　 be nervous about　　

11. nerve　 神经　 lose one's nerve = lose one's courage 失去勇气　

　 have the nerve to do 有胆量做…

10. neglect one's duties 　neglect one's meals and sleeps 废寝忘食 　neglect to do = forget to do

9. negative　 否定的，消极的，give a negative answer 否定回答　 negative criticism 消极批评

8. meet one's needs 满足需求　　 be in need of 需要　　　 There is no need for sb to do ...　

7. necessary　 必要的　　 if necessary 如有必要　　 It's necessary that sb ( should ) do...

6. essentially　 本质地　　　 He is essentially kind. 他本质上是好的。

5. necessarily　 必要地　 It's not necessarily so.未必如此。　 The rich are not necessarily happy.

4. not nearly = far from　 远非　 It's not nearly so easy as you think.这决非你想的那样简单。