Each system has its own measurement nouns, as shown in the table below. Their abbreviations are shown in brackets.

	metric units	imperial units
size/distance	millimetre (mm) centimetre (cm) metre (m) kilometre (km)	inch (in or ") foot (ft or ')   yard (yd) mile (m)
area	hectare (ha)	acre (a)
volume	millilitre (ml) centilitre (cI) litre (I)	fluid ounce (fl oz) pint (pt) quart (q) gallon (gal)
weight	milligram (mg) gram (g) kilogram (kg) tonne (t)	ounce (oz) pound (lb) stone (st) hundredweight (cwt) ton (t)

If you are using metric units, you use decimal numbers. For example, you say that something is 1.68 metres long or weighs 4.8 kilograms. With imperial units, fractions are often used instead, for example six and three-quarter inches or one and a half tons of wheat.

Kilo is sometimes used instead of 'kilogram', and metric ton instead of 'tonne'.

In the United States, the metric system is not commonly used, except for military, medical, and scientific purposes. The spellings meter and liter are used instead of 'metre' and 'litre'. The terms 'stone' and 'hundredweight' are very rarely used. Note that U.S. pints, quarts, and gallons are slightly smaller than British ones.

size

When you want to state the size of something, you usually use a number, a measurement noun, and an adjective. The verb you use is be.

The water was fifteen feet deep.

One of the layers is six metres thick.

As well as the plural form feet, the singular form foot can be used with numbers.

The spears were about six foot long.

If you are expressing size using feet and inches, and using the form foot, you don't have to say 'inches'. For example, you can say that something is two foot six long. However, don't say 'two feet six' or 'two foot six inches'.

I'm five foot three.

He's immensely tall, six feet six inches.

The following adjectives can be used after measurement nouns showing size:

deep

high

long

to

thick

wide

BE CAREFUL! Don't use adjectives such as 'narrow', 'shallow', 'low', or 'thin'. When mentioning someone's height, you can use the adjective tall or leave it out.

She was six feet tall.

He was six foot six.

BE CAREFUL! Don't use the adjective 'high' for people. Use long for babies, not 'tall'.

When describing how wide something is, you can use across instead of 'wide'.

The squid was 21 metres long with eyes 40 centimetres across.

Instead of using an adjective when stating size, you can use one of the following prepositional phrases after the measurement noun.

in depth

in height

in length

in thickness

in width

They are thirty centimetres in length.

He was five feet seven inches in height.

When asking a question about the size of something, you use how and the adjectives listed earlier. You can also use the less specific adjective big.

How tall is he?

How big is it going to be?

size of circular objects and areas

If you are talking about the size of a circular object or area, you can give its circumference (edge measurement) or diameter (width) using in circumference or in diameter. You can also say that something has a radius (half the diameter) of a particular length. However, don't say 'in radius'.

Some of the lakes are ten or twenty kilometres in circumference.

They are about nine inches in diameter.

It had a radius of fifteen kilometres.

 

size by dimensions

If you want to describe the size of an object or area fully, you can give its dimensions; that is, you can give the measurements for its length and width, or length, width, and depth. When you give the dimensions of an object or area, you separate the figures using and, by, or the multiplication sign x (pronounced 'by'). You use the verb be or measure. You can use adjectives such as long and wide or leave them out.

Each frame was four metres tall and sixty-six centimetres wide.

The island measures about 25 miles by 12 miles.

The box measures approximately 26 inches wide x 25 inches deep x 16 inches high.

area

Area is often expressed by using square in front of units of length. For example, a square metre has the same area as a square whose sides are one metre long.

He had cleared away about three square inches.

They are said to be as little as 300 sq cm.

If you are talking about a square object or area, you can give the length of each side followed by the word square.

Each family has only one room eight or ten feet square.

...an area that is 25 km square.

When talking about large areas of land, the words hectare and acre are often used.

In 1975 there were 1,240 million hectares under cultivation.

His land covers twenty acres.

volume

The volume of an object is the amount of space it occupies or contains. Volume is usually expressed by using cubic in front of units of length. For example, you can say 10 cubic centimetres or 200 cubic feet.

Its brain was close to 500 cubic centimetres (49 cubic inches).

Units of volume such as litre and gallon are used to refer to quantities of liquids and gases.

Wine production is expected to reach 4.1 billion gallons this year.

The amount of air being expelled is about 1,000 to 1,500 mls.

distance

You can show the distance from one thing to another by using a number and measurement noun in front of from, away from, or away.

The hotel is 60 yds from the beach.

These offices were approximately nine kilometres away from the city centre.

She sat down about a hundred metres away.

Distance can also be shown by stating the time taken to travel it.

It is half an hour from the Pinewood Studios and forty-five minutes from London.

They lived only two or three days away from Juffure.

The method of travelling can be stated to be more precise.

It is less than an hour's drive from here.

It's about five minutes' walk from the bus stop.

If you want to know the distance to a place, you use how far, usually with from, or with impersonal it and to.

How far is Chester from here?

How far is it to Charles City?

distance and position

To show both the distance and the position of something in relation to another place or object, the distance can be stated in front of the following prepositions:

above      beneath      off      under      across      beyond      out of     underneath      along      down      outside      up      behind      inside      over      below      into      past

He guessed that he was about ten miles above the surface.

Maurice was only a few yards behind him.

All the words in the list above, except 'across', 'into', 'over', and 'past', can be used as adverbs after the distance.

The adverbs apart, in, inland, offshore, on, and out can also be used.

These two fossils had been lying about so feet apart in the sand.

We were now forty miles inland.

A few metres further on were other unmistakable traces of disaster.

The distance can also be stated in front of phrases such as north of, to the east of, and to the left.

He was some miles north of Ayr.

It had exploded 700 yards to their right.

weight

When you want to state how much an object or animal weighs, you use the verb weigh.

The statue weighs fifty or more kilos.

The calf weighs 50 lbs.

When you want to state how much a person weighs, you can use weigh or be. In Britain, you usually use the singular form stone.

He weighs about nine and a half stone.

You're about ten and a half stone.

If you express weight using stones and pounds, you can leave out the word 'pounds'. For example, you can say that someone weighs twelve stone four.

Don't say 'two-pounds heavy', but you can say 'two pounds in weight'

I put on nearly a stone in weight.

In the United States, all weights are normally expressed in pounds or tons. 'Stone' is very rarely used.

Philip Swallow weighs about 140 pounds.

Americans often omit the words 'hundred' and 'pounds' when talking about a person's weight.

I bet he weighs one seventy, at least.

When asking about the weight of something or someone, you can use how much and weigh.

How much does the whole thing weigh?

You can also use how heavy.

How heavy are they?

temperature

You express temperature using either degrees centigrade (often written 5°C), or degrees Fahrenheit (often written 5°F). In everyday language the metric term centigrade is used, whereas in scientific language Celsius is used to refer to the same scale of measurement.

The temperature was still 23 degrees centigrade.

It was 95°C, and felt much colder.

If the scale is known, degrees can be used by itself.

It's 72 degrees down here and we've had a dry week.

In cold weather, temperatures are often stated as degrees below freezing or degrees below zero. Note that in Britain below zero usually means below zero Celsius, but in the US below zero means below zero Fahrenheit, which is much colder.

...when the temperature is fifteen degrees below freezing.

It's amazingly cold: must be twenty degrees below zero.

speed, rates, and ratios

You talk about the speed of something by saying how far it travels in a particular unit of time. To do this, you use a noun such as kilometre or mile, followed by per, a, or an, and a noun referring to a length of time.

Wind speeds at the airport were 160 kilometres per hour.

He'd been driving at 10 miles an hour.

When writing about speeds, rates, or pressures, you can use the symbol '/' instead of 'per' between abbreviations for the units of measurement.

...a velocity of 16o km/sec

Per, a, and an are also used when talking about other rates and ratios.

...a heart rate of 70 beats per minute.

He earns thirty dollars an hour.

Per can also be used in front of a word that does not refer to a length of time or a unit of measurement.

In Indonesia there are 18,000 people per doctor.

I think we have more paper per employee in this department than in any other.

Per head or a head are often used instead of 'per person' or 'a person'.

The average cereal consumption per head per year in the U.S.A. is 900 kg.

You can also use to the when you are talking about rates and ratios.

The exchange rate would soon be $2 to the pound.

measurements used before and after nouns

Expressions showing size, area, volume, distance, and weight can be used as modifiers in front of a noun.

...a 5 foot 9 inch bed.

15 cm x 10 cm posts would be ideal.

...a 2-litre engine.

You can use adjectives like 'long' and 'high', but you do not have to.

If the expression consists simply of a number and a measurement noun, it is often hyphenated.

...a five-pound bag of lentils.

We finished our 500-mile journey at 4.3o p.m. on the 25th September.

BE CAREFUL!

The measurement noun is singular, not plural, even though it comes after a number. For example, don't say 'a ten miles walk'. Say a ten-mile walk.

However, the plural form is used in athletics, because the measurement is really the name of a race. For example, 'the 100 metres record' means 'the record for the 100 metres (race)'.

He won the 100 metres breaststroke.

You can use measurement expressions, usually ending in an adjective or a phrase beginning with in, after a noun.

There were seven main bedrooms and a sitting-room fifty feet long.

...a giant planet over3o,000 miles in diameter.

You can also show the area or weight of something using -ing forms such as covering, measuring, or weighing.

...a large park covering 40,000 square feet.

...a square area measuring 900 metres on each side.

...an iron bar weighing fifteen pounds.

You can also show the area or volume of something using a phrase beginning with of

...industrial units of less than 15,000 sq ft.

...vessels of 100 litres.

size of something abstract

If you want to show how great something is, you use of.

...speeds of nearly 100 mph.

...an average annual temperature of 2050.

...an increase of 10 percent.

You can also sometimes use a modifier, for example when talking about percentages or salaries.

...a 71 percent increase in earnings.

 ...his £ 25,000-a-year salary.

measurement nouns before 'of '

Measurement nouns are often used in front of of to refer to an amount of something which is a particular length, area, volume, or weight.

...20 yds of nylon.