It’s an honorary. The rule for choosing between “a” and “an” is based on the pronunciation of the word that follows, and not on how it is spelled.

It’s an honor. The rule for choosing between “a” and “an” is based on pronunciation, not spelling. Since the word honor begins with a silent "h", it takes the indefinite article "an".

It’s an honest. Since “honest” starts with a silent “h”, we use the indefinite article “an”.

Both "a historical" and "an historical" are used, but the article "a" is far more common, particularly in American English.

Most American English speakers pronounce “historic” with an audible “h”, so they generally say and write “a historic”. Some British English speakers, by contrast, pronounce “historic” without the “h”.

It's a useless. The adjective useless begins with a consonant sound, a "you" sound, so it takes the indefinite article "a".

hoose the article ("a" or "an") that best suits your own pronunciation. Remember, we use “a” with words that begin with a consonant sound.

The British say a herbivore since the "h" is silent. An American English speaker, however, typically chooses the article (a/an) that best suits his or her own pronunciation.

The noun herbicide is more often pronounced with a sounded "h"; thus, "a herbicide" is more common. However, some American English speakers don't pronounce the "h" and say "an herbicide". Remember, the rule for using a or an is based