掌握化学用语是学好化学的关键,下列化学用语与含义相符的是( )
A:Fe3O4﹣﹣四氧化三铁
B:2H﹣﹣2个氢元素
C:O2﹣﹣2个氧原子
D:Na+1﹣﹣钠离子
In order to make the garden beautiful, many trees and flowers are g____ in it.
一 I'm ________ to speak in front of many people.
— Don't worry, John. You can do it.