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.placebo n.安慰剂；安慰话
The placebo has been found to work with a lot of different cases.
人们已发现安慰剂能在很多不同的病例中发挥作用。
3.complementary a.补充的；互补的
His personality is complementary to hers.
他的个性与她的相反相成。
4.rigorous a.严格的；严厉的
The planes have to undergo rigorous safety checks.
这些飞机得接受非常严格的安全检查。
5.crystal n.水晶；结晶体
I lost my crystal necklace at the party.
我在晚会上丢失了水晶项链。
