Sometimes, we don't need to be precise or we don't have the exact data, in these cases, we can use vague language to express things in an inexact way.

List of idiomas related to landscape. A list of idioms in alphabetical order can be found following this link Idioms - alphabetical order

Historical: Refers to any event, person, building ... in the past.

Many important historical documents were destroyed when the library was bombed.
She specializes in historical novels set in 18th-century England.

Economic: Any thing related to economy, trade, industry or money

The economic forecast for next year is not good.

List of idioms related to feelings. A list of idioms in alphabetical order can be found following this link. Idioms - alphabetical order

Relative clauses help to connect two separate ideas which might be expressed in two separate sentences.