第二节：语法填空      

In the past few years, quite a number of men and women have chosen to do something less competitive. They are afraid that the stress and strains of work will rob them ____11_ ___ joy and happiness and ____12  ____ them harm both physically and mentally.

In fact, however, stress isn’t the bad thing ____13____ it is often supposed to be. Above all, ____14____ it gets out of control, a certain amount of stress is vital to provide motivation and challenge, and to give purpose and significance to ____15____, otherwise meaningless, idle life. ____16___, people under stress tend to express their full range of potential and to actualize their own _____17____(person) worth—the very aim of a human life.

Stress is a natural part of everyday life and _____18 ___ is no way to avoid it. What we can do is ____19____(develop) our adaptive abilities to deal with it rather than to escape ____20___ it.

互联网上电子邮件服务使用的协议是______。

A．SMTP
B．SNMP
C．IGMP
D．RUP