1.alternative a.两者择一的；供选择的

We have the alternative plans of having a picnic or taking a boat trip.
我们在去野餐或者去乘船旅游两个计划中只能选一。

2.client n.委托人；客户

If a lawyer has plenty of clients, he grows rich.
律师如果有大量的诉讼委托人，就会财源不断。

3.irritation n.刺激；烦恼

Discontinue use if irritation or rash appear.
如果发生刺激或丘疹请停止使用。

4.collaborate v.合作；通敌

She collaborated with her sister/She and her sister collaborated on a biography of their father.
她和姐姐合作写父亲的传记。

5.automatic a.自动的；无意识的

This heating system has an automatic temperature control.
这个暖气系统有自动化的温度调节系统。