The words "and" and "or" are coordinating conjunctions. In Italian, there are two different forms for each of these two words depending on the word that follows them.
The Italian verb sapere usually means "to know." It has irregular conjugations in just about every tense and mood, and a somewhat different meaning in the past.
The letter combination GH is pronounced like the hard English g in “granite.”
Italian has a dozen verbs with an irregular infinitive that ends in -arre, a contraction of the original infinitive ending -aggere. Many conjugations for these verbs are based on that original infinitive.
When, where, why, how? Use interrogative adverbs to ask these informational questions.