Sentence word order: Subject + verb + object.

In questions and after certain adverbs we usually place a verb before the subject

The form of 'be' agrees with the following noun. If there is more than one noun, the form of 'be' agrees with the first noun in the list.

We use 'it' + 'be' to introduce information about:
-weather/environment.
-Time/dates.
-Conditions/situations.
-Distance.

We can make a negative with not + -ing.

But we use NO + -ing to explain that something is impossible or not allowed.