中国大学MOOC: _________ is considered as the glass former.
举一反三
- _________ is considered as the glass former. A: ZnO B: CaO C: SiO2 D: Al2O3
- It is considered inappropriate for a former president to ________ in commerce.
- 中国大学MOOC: The most expensive glass is .
- 中国大学MOOC: There is little water in the glass, ____?
- 中国大学MOOC: Glass is _________ or delicate. That is, it is easily broken.