Read Collins Cobuild English Grammar Online
Authors: Collins
Note that
half
is always used with
of
before a pronoun (see paragraph
2.242
).
fractions expressed in figures
2.248
You can write a fraction in figures, for example
1/2
,
1/4
,
3/4
, and
2/3
. These correspond to
a half
,
a quarter
,
three quarters
and
two thirds
respectively.
expressing percentages
2.249
Fractions are often given in a special form as a number of hundredths. This type of fraction is called a
percentage
. For example,
three hundredths
, expressed as a percentage, is
three per cent
. It can also be written as
three percent
or
3%
.
A half
can be expressed as
fifty per cent
,
fifty percent
, or
50%
.
90 percent
of most food is water.
About
20 per cent
of student accountants are women.
Before 1960
45%
of British trade was with the Commonwealth.
You use percentages on their own as noun phrases when it is clear what they refer to.
Ninety per cent
were self employed.
…interest at
10%
per annum.
Talking about measurements
2.250
You can refer to a size, distance, area, volume, weight, speed, or temperature by using a number or quantity expression in front of a
measurement noun
. Measurement nouns are countable.
They grow to twenty
feet
.
…blocks of stone weighing up to a hundred
tons
.
Reduce the temperature by a few
degrees
.
Average annual temperatures exceed
20° centigrade
.
Other ways of expressing distance are explained in paragraphs
6.91
to
6.92
. Measurement nouns referring to size, area, volume, and weight are often used in
partitive structures
(see paragraphs
2.194
to
2.207
) such as
a pint of milk
and
a pound of onions
. They are also used in phrases beginning with
of
(see paragraph
2.283
).
imperial and metric measurements
2.251
There are two systems of measurement used in Britain – the
imperial system
and the
metric system
. Each system has its own measurement nouns.
Here is a list of the imperial units of measurement indicating size, distance, area, volume, and weight:
inch
foot
yard
mile
~
acre
~
pint
quart
gallon
~
ounce
pound
stone
hundredweight
ton
Note that the plural of
foot
is
feet
, but
foot
can also be used with numbers. Similarly
stone
is usually used instead of
stones
.
Here is a list of the metric units of measurement indicating size, distance, area, volume, and weight:
millimetre
centimetre
metre
kilometre
~
hectare
~
millilitre
centilitre
litre
~
milligram
gram
kilogram
tonne
after linking verbs
2.252
Measurement nouns are often used after
linking verbs
such as
be
,
measure
and
weigh
.
The fish
was
about eight feet long.
It
measures
approximately 26 inches wide x 25 inches long.
…a square area
measuring
900 metres on each side.
It
weighs
fifty or more kilos.
The use of adjectives after linking verbs is explained in paragraphs
3.132
to
3.137
.
adjectives after measurements
2.253
When measurement nouns that give the size of something are used after a linking verb, they are often followed by an adjective that makes it clear exactly what the measurement refers to
He was about
six feet tall
.
The spears were about
six foot long
.
…a room
2 metres wide
.
The water was
fifteen feet deep
.
…a layer of stone
four metres thick
.
Here is a list of the adjectives that follow measurement nouns indicating size:
broad
deep
high
long
tall
thick
wide
Note that you do not say
two pounds heavy
but
two pounds in weight
instead.
phrases beginning with
in
after measurements
2.254
Similarly, some measurement nouns can be followed by prepositional phrases beginning with
in
.
…a block of ice one cubic foot
in size
.
I put on nearly a stone
in weight
.
They are thirty centimetres
in length
.
…deposits measuring up to a kilometre
in thickness
.
It was close to ten feet
in height
.
Here is a list of phrases beginning with
in
used after measurements:
in area
in breadth
in depth
in distance
in height
in length
in size
in thickness
in volume
in weight
in width
measurement nouns used as modifiers
2.255
Measurement nouns can also be used as modifiers in front of a noun when you want to describe things in terms of their measurements.
…a
5 foot 9 inch
bed.
…
70 foot high
mounds of dust.
…
12 x 12 inch
tiles.
…a
five-pound
bag of lentils.
Note that the measurement noun is singular.
USAGE NOTE
2.256
If you want to describe fully the size of an object or area, you can give its dimensions; that is, you give measurements of its length and width, or length, width, and depth. When you give the dimensions of an object, you separate the figures using
and
,
by
, or the multiplication sign
x
.
…planks of wood about
three inches thick and two feet wide
.
The island measures about
25 miles by 12 miles
.
Lake Nyasa is
450 miles long by about 50 miles wide
.
The box measures approximately
26 inches wide x 25 inches deep x 16 inches high
.
If you are talking about a square object or area, you give the length of each side followed by the word
square
.
Each family has only one room eight or ten feet
square
.
The site measures roughly 35 feet
square
.
Square
is used in front of units of length when expressing area.
Cubic
is used in front of units of length when expressing volume.
…a farm covering 300
square miles
.
The brain of the first ape-men was about the same size as that of a gorilla, around 500
cubic centimetres
.
You express temperature in degrees, using either degrees centigrade, or degrees Fahrenheit. Note that in everyday language the metric term
centigrade
is used to indicate temperature, whereas in scientific language the term
Celsius
is used which refers to exactly the same scale of measurement.
2.257
You talk about the speed of something by saying how far it can travel in a particular unit of time. To do this, you use a noun such as
mile
or
kilometre
, followed by
per
,
a
, or
an
, and a time noun.
The car could do only forty-five
miles per hour
.
Wind speeds at the airport were 160
kilometres per hour
.
Warships move at about 500
miles per day
.
Talking about age
2.258
When you want to say how old someone is, you have a choice of ways in which to do it. You can be exact or approximate. Similarly, when you want to say how old something is, you can use different ways, some exact, and some approximate.