Answer: Air and water <em><u>are</u></em> necessary for life.
Explanation:
Air and water are a plural subject because a subject made up of nouns joined by 'and' makes a compound subject, unless that subject's intended sense is singular, therefore the verb must be conjugated in the plural: "They are".
<h2><em>Eiztari</em></h2>
Because the tree started to get very old and they didn’t want the tree to rot
<span>Taking the verb BEAT as an example, it is possible to classify it according to its principal parts;
-infinitive: (to) Beat -present: beat / beats-past: beat-present participle or gerund: beating-past participle: had beaten<span>
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