Incapable of being seen through – opaque or transparent

In most university courses there are two ways of being assessed, one is oral, the other is through…?

One who knows or sees everything – omniscient or omnipresent

Which major branch of science deals with the classification of living things?

The thing which catches fire easily – irresistible or inflammable

Would a supermarket, a café, or a bookstore probably have the widest range of products available?

A place where birds are kept – aquarium or aviary

How would most people travel to work each day, in big cities like Hong Kong, Tokyo, and New York?

A post which carries no salary – honorary or honorable