used when referring to someone or something for the first time in a text or conversation

a man came out of the room

it has been an honour to meet you

we need people with a knowledge of languages

used to indicate membership of a class of people or things

he is a lawyer

this car is a BMW

in, to, or for each; per (used when expressing rates or ratios)

typing 60 words a minute

a move to raise petrol prices by 3p a litre

the first letter of the alphabet

a shape like that of a capital A

an A-shape

the sixth note of the diatonic scale of C major. The A above middle C is usually used as the basis for tuning and in modern music has a standard frequency of 440 Hz

the form of the indefinite article used before words beginning with a vowel sound

Andaman and Nicobar Islands