The guide showed the travelers _____ of the factory.
---May I look at the menu for a little while?--- Of course, _______, sir.
_______ children get older, they become more and more interested in everything.
_______ has been known that ______ other waste found in the ocean, the plastic does not break down.
It is a good plan in theory, but it remains _______ whether it works in practice.
As senior three students, it is important to ______ a good state of mind.