Page 398 - Practical English Usage 3ed - Michael Swan, Oxford

1 inch (1 in) =2.5 cm
12 inches =1 foot (30 cm)
3 feet (3 ft) =1 yard (90 cm)
5,280 feet /1,760 yards =1 mile (1.6 kmJ
5 miles =8 km
1 ounce (1 oz) =28 gm
16 ounces = 1 pound (455 gm)
2.2 pounds (2.2Ib) =1 kg
14 pounds (14 lb) =1 stone (6.4 kg) (BrE only) 1 British pint =56.8 cl
1 US pint =47.3 cl
8 pints (8 pt) = 1 gallon
1 British gallon =4.55 litres
1 US gallon =3.78 lUres
1 acre =4,840 square yards =0.4 hectares
1 square mile =640 acres =259 ha
British people measure their weight in stones and pounds or (more recently) in kilograms; Americans just use pounds. Height is measured in feet; distance can also be measured in feet, but longer distances are often measured in yards, especially in British English.
I weigh eight stone six. (NOT ••• eig.'1t sttmes six)
We are now flying at an altitude of28,000 feet.
The car park's straight on, about 500 yards on the right.
19 area and volume
We say, for example, that a room is twelve feet by fifteen feet, or that a garden is thirty metres by forty-eight metres.
A room twelve feet by twelve feet can be called twelve feet square; the total area is 144 square feet.
A container 2 metres by 2 metres by 3 metres has a volume of 12 cubic metres.
20 a and per
When we relate two different measures, we usually use alan; per is often used in formal writing.
It costs two pounds a week. (OR ••• £2 per week.)
We're doing seventy miles an hour. (OR ••• 70 miles per Iwur / mph.)
21 numbers not used as complements after be
Numbers are used as subjects or objects, but not usually as complements after be.
I've got three sisters. (NOT My sisters are three.)
There are twelve of us in my family. (More natural than We are twelve. ..)
22 spoken calculations
Common ways of saying calculations in British English are:
2 + 2 =4 7 - 4 =3
Two and two is/are four. (informal) Two plus two equals/is four. (formal)
Four from seven is/leaves three. (informal) Seven take away four is/leaves three. (informal) Seven minus four equals/is three. (formal)
numbers 389
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