English question, please help?

If you can identify two items then you have just counted them. Countable or uncountable nouns - it doesn't matter so long as there ARE at least two of them you can count them.

Water and air are usually uncountable but together they ARE two nouns. TWO uncountable nouns ARE countable. There ARE two of them. They ARE both important.

Water air and fire ARE THREE uncountable nouns that can be COUNTED when they ARE together,

1, 2, 3, 4 earth, water, air, fire.



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"water and air are important" is correct in ordinary standard English.

Note: there is a category of combinations forming a single thing such as "bacon and eggs" that become singular.

"Bacon and eggs is my favorite breakfast,' for instance.

Although unusual, it might be possible to construct a sentence combining water and air in this way. Perhaps:

"Water and air is the combination necessary for life."

"Water and air are important" is correct. For a detailed reference on 'uncountable' nouns or 'mass' nouns as they are also called, see below. In this case, both 'water' and 'air' are used in a singular sense, though both have plural forms.

Water and air are important <- correct.
so apparently that is standard case.

From my knowledge it should be WATER AND AIR ARE IMPORTANT

are is correct