Page 123 - Practical English Usage 3ed - Michael Swan, Oxford

110 both
1 meaning
Both means 'each of two'.
Both my parents were born in Scotland.
We do not normally use both when the meaning is not 'each'.
My two brothers carried the piano upstairs. (More natural than Both my
brothers carried the piano upstairs - they didn't each carry it separately.)
2 both and both o f
Before a noun with a determiner (e.g. the, my, these), both and both ofare both possible.
She's eaten both (0!J the chops. Both (0!J these oranges are bad.
He lost both (0!J his parents when he was a child.
We often drop the or a possessive after both; ofis not used in this case.
She's eaten both chops. (NOT ••• bBffl ttfehBps) He lost both parents when he was a child.
3 the not used before both
Note that we do not put the before both.
both (the) children (NOT #re bBth ehiltlren)
4 personal pronouns: both o f
With personal pronouns, we use both of+ us/you/them. Both ofus/you/them can be a subject or object.
Both ofthem can come tomorrow.
She's invited both ofus. Mary sends both ofyou her love. We can put both after pronouns used as objects.
She's invited us both. Mary sends you both her love.
But this structure is not used in complements (after be) or in short answers.
Who broke the window - Sarah or Alice?-It was both ofthem. (NOT ••• #rem h6th.)
Who did she invite?-Both ofus. (NOT Us b6fh.)
5 both with a verb
When both refers to the subject of a clause, it can go with the verb, in 'mid- position' (for details of word order, see 24).
We can both swim. Those oranges were both bad.
The children have both gone to bed. My sisters both work in education. Note that these meanings can also be expressed by using both (oj) with a subject (see above).
Both o f us can swim. Both (0!J the children have gone to bed.
6 negative structures
Instead of both . .. not, we normally use neither (see 372). Neither ofthem is here. (NOT BBth ttfthem tlFe ItBt iteFe.)
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