Italian Cardinal Numbers
Cardinal numbers are the basic numbers that we use in counting, money and math. Cardinal numbers can also be used as adjectives to quantify the amount of an object. Let's go over first the numbers 0 to 100 in Italian:
1: uno (the feminine form is una)
For numbers 31 and over, they follow the same pattern as lower numbers: if the second number begins with a vowel, the final letter of the first number is dropped; if the second number begins with a consonant, the final letter of the first number is kept. If the number is being used as an adjective, it goes before the noun it is modifying.
Now, let's go over numbers 102 and above:
1.000.000: un milione
1.000.000.000: un miliardo
Notice that for 102, the format is similar to forming double digit numbers. If we have multiple thousands, we use the plural form mila. Once numbers break into the thousands, the numeral numbers in Italian use a “.” as a separator, comparable to the “,” in English.
Most numbers are written as one word, except for numbers with milione and miliardo. The numbers are separated with e (and). For example:
un milione e duecento (1.000.200)
Also, if milione and miliardo are quantifying a noun, the number and noun are separated with di (of):
due milioni di abitanti (two million inhabitants)
In addition, numbers in Italian are masculine.
Italian Ordinal Numbers
Ordinal numbers are different from cardinal numbers: they are used to rate objects, such as first, second and third. In addition, when preceded by the word circa (about), ordinal numbers can be used to give an approximate quantity. Let's go over some of the ordinal numbers in Italian:
To form an ordinal number above 10º, we take the cardinal number, remove the final vowel and add -esimo. The exception to this rule are numbers that end with -tre; in those cases, the final vowel is kept. Let's use the number 20 as an example: the cardinal number for 20 is venti. Now to make it an ordinal number, we remove the -i and add the -esimo. Now it becomes ventesimo. Now if we want to change the number 23, it starts as ventitré in cardinal form and we add -esimo: ventritreesimo. We drop the accent for an easier pronunciation.
Most of the time, an ordinal number comes before the noun it qualifies, like cardinal numbers. However, ordinal numbers go after the names of important people, such as royalty. For example, if we wanted to talk about Queen Elizabeth II of England, we would say regina Elisabetta secondo; in print, it would be regina Elisabetta II.
In addition, the endings of ordinal numbers change, depending on the gender and amount of the noun.
When making fractions, the cardinal number is the numerator and the ordinal number is the denominator. For example:
2/3 = due terzi
Mezzadri, Marco. Essential Italian. Guerra Edizioni, 2004