english has two sets of numbers – one for counting things and one for describing their order. you have already encountered these (one, two, three, first, second, third) when we talked about ages and birthdays. now we will look at the rest of the numbers in english and how they are used, especially larger numbers and how to say and write them.
english numbers are usually grouped in sets of three but sometimes sets of two are used.
1000 is said “one-thousand” or “a thousand” and 1000000 is “a million” but 2400 is usually “twenty-four-hundred” and 5621 will probably be read as “fifty-six-twenty-one”. in more formal situations, these will become “two-thousand-four-hundred” and “five-thousand-six-hundred-twenty-one” but the first case is far more common.
other than this exception for four-digit numbers, there are three places you will usually see large groups of numbers – large-scale approximations, phone numbers and scientific or mathematical work.
for large-scale approximations, the grouping by three-digit blocks is very important and many numbers can be read at least two ways. which you choose when you speak them is usually unimportant but it is necessary to understand them all because which another uses is unpredictable.
7000000 – seven-million
7800000 – seven-point-eight-million / seven-million-eight-hundred-thousand
large numbers with at least six digits are often read as decimal parts of millions, billions, etc. thousands are never read this way – 6700 will never become “six-point-seven-thousand”. this is why the two-and-two grouping of four-digit numbers is so common. 6700 can be read “six-thousand-seven-hundred” but “sixty-seven-hundred” is far more likely to be used.
many english-speakers add extra words like “and” between digits but this is a colloquial trend and is generally disappearing as english becomes more standardized. as numbers are written in groups of three, it is important to know the names for each of these groups. beginning from the smallest, these are the common names for large numbers in english.
1000 (thousand), 1000000 (million), 1000000000 (billion), 1000000000000 (trillion)
while larger numbers are certainly possible, they are unlikely to be written as actual numbers, using words or scientific notation depending on the circumstance. in typical daily conversation, anything beyond a billion is very rare and beyond a trillion would be extremely unusual written as digits to be read.
phone numbers are read in two possible ways – as individual numbers or groups of two.
773.815.1523 – seven-seven-three-eight-one-five-one-five-two-three or seven-seven-three-eight-one-five-fifteen-twenty-three
904-114-1710 – nine-oh-four-one-one-four-one-seven-one-oh or nine-oh-four-one-one-four-seventeen-ten
which of these alternatives you choose makes no real difference but it is again important to understand both options as they are commonly-heard.
regular large numbers are read in groups of three with the words simply linked together. here are some examples.
824427 – eight-hundred-twenty-four-thousand-four-hundred-twenty-seven
162253 – one-hundred-sixty-two-thousand-two-hundred-fifty-three
982619 – nine-hundred-eighty-two-thousand-six-hundred-nineteen
614422982 – six-hundred-fourteen-million-four-hundred-twenty-two-thousand-nine-hundred-eighty-two
17285111459 – seventeen-billion-two-hundred-eighty-five-million-one-hundred-eleven-thousand-four-hundred-fifty-nine
ordering numbers show up in english in a few different contexts. the main one, of course, is talking about where things are related to each other.
the book i want is the fourth from the right.
that was my second piece of cake.
she came first in the hundred-meter sprint.
i live on the thirty-second floor.
the other place it appears is in dates.
my birthday is january fourteenth.
christmas is december twenty-fifth.
what are you doing on the ninth?
the exception, where counting numbers are used instead is when the number follows the noun it’s counting.
i live on floor six.
i live in house seventeen.
you’re staying in room fourteen-thirty-five.
two other places ordering numbers are used are when talking about compared ages in a family and times when activities occur.
i am my mother’s second child.
my dad’s first child was my older sister.
first let’s go to the movies then walk in the park.
i want to stop at my house first.
we have already looked at the first set of ordering numbers. the rest are built using the same pattern and there are no significant exceptions.
first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth
eleventh, twelfth, thirteenth, fourteenth, fifteenth…
twentieth, thirtieth, fortieth, fiftieth, sixtieth, seventieth, eightieth, ninetieth, hundredth
thousandth, millionth, billionth, trillionth
twenty-first, twenty-second, twenty-third, hundred-first, hundred-second, hundred-thirteenth, hundred-fourteenth, hundred-twenty-fifth, hundred-twenty-sixth
when building these ordering numbers, only the last number is ever changed from its regular counting form. above thirteen, all numbers ending in 1 take first, 2 take second, 3 take third and others all end in th.
there is one other form of ordering numbers you occasionally see when talking about ideas. instead of “first idea” and “second idea” they are sometimes called “primary”, “secondary” and “tertiary”. this set continues but those three are the only ones still in modern common usage. this is a somewhat-advanced concept but when you see these words you can think of them as equivalents of “first”, “second” and “third” as the meaning is the same.
this problem is of primary concern.
the idea is secondary.
this is a tertiary difficulty and we don’t need to talk about it.