A pair of / a packet of...

'A pair of' and 'a packet of' are quantifier phrases used to describe a specific quantity or grouping. They introduce a noun phrase and tell us how many or what kind of group is being referred to.

• 'A pair of' usually refers to two connected or matching items considered as one unit (e.g., a pair of shoes).
• 'A packet of' indicates a small packaged quantity of items or an amount of an uncountable substance (e.g., a packet of biscuits, a packet of sugar).
• These phrases are common in business and everyday English for ordering, inventory, and describing equipment.

Remember how each phrase interacts with the noun and verb:

• 'A pair of' + plural noun: the noun is usually plural (a pair of scissors), but the verb often agrees with 'pair' (singular): 'A pair of scissors is on the desk.'
• 'A packet of' + plural or uncountable noun: use 'of' and keep the noun in the normal form: 'a packet of biscuits' or 'a packet of sugar.'
• When talking about the individual items, you can use the plural noun: 'The scissors are sharp.'

Focus on the grammatical subject (pair/packet) for verb agreement.

Learners often make predictable errors with these phrases. Watch for:

• Incorrect verb agreement: Saying 'A pair of scissors are...' instead of 'A pair of scissors is...'.
• Plural mistakes: Using singular after 'a pair of' ('a pair of scissor' is wrong).
• Wrong use of 'packet': Confusing 'packet' with 'pack' or omitting 'of' ('a packet sugar' is wrong).
• Countability errors: Using plural forms with uncountable nouns after 'packet' (e.g., 'a packet of sugars' is usually incorrect).

Check: subject (pair/packet) for verb, noun form after 'of', and whether the noun is countable.