The other day we mentioned that the words два/две ‘two’ are followed by a noun in a form that resembles the genitive singular. What's really freaky, though, is that if you put an adjective between the number and the noun, you don't use the genitive singular. So what for do you use? Well, that depends...

If you are dealing with masculine or neuter nouns, then you have to use an adjectival form that copies the genitive plural:

If you are dealing with feminine nouns, it is usually best to use an adjectival form that copies the nominative plural:

Here are some sample sentences:

¹ You will sometimes also encounter две новых машины, аlthough новые is better style these days.

Every student of the Russian language knows that Russian nouns have a singular form and a plural form. Many don't know that a thousand years ago those nouns had a “dual form” as well. The dual meant “two of an item”, whereas the plural meant “more than two of an item”. Thus града meant “two cities” and сътѣ meant "two hundreds" and сестрѣ meant “two sisters”. At that time the number дъва was an adjective that agreed with masculine dual nouns and emphasized twoness, and дъвѣ was an adjective that agreed with neuter/feminine nouns and emphasized twoness as well. So back then we had дъва града “two cities”, дъвѣ сътѣ “two hundreds”, and дъвѣ сестрѣ “two sisters”.

Over the centuries time/entropy/life disrupted all that beautiful grammatical symmetry. The "-a" form of masculine nouns often resembled the genitive singular, so nowadays the numbers два/две are followed by nouns in a form that generally coincides with the genitive singular form. The gender association of the numbers shifted as well: nowadays два is used with masculine and neuter nouns, and две is only used with feminine nouns. Here are some sample sentences:

Let's say a young Russian student is composing an essay and decides to write “I want to earn a billion dollars” in Russian. He knows the word for million is миллион, so he figures a billion must be биллион, but, being an enterprising student, he quickly double-checks his Russian dictionary. He is pleased to note that the word is exactly as he expected, so he writes «Я хочу заработать биллион долларов.» Alas, he has made an error. Even though you can find the word биллион in Russian dictionaries, people rarely use it. Instead they say миллиард:

If you are translating from English to Russian, you must be quite careful if the source document has the word billion in it. In the US the word billion always means 1,000,000,000. That's not necessarily true in other English-speaking countries. For most of the nineteenth and twentieth centuries in England the word meant 1,000,000,000,000. (In the States we call that a trillion). The US system is known as the “short scale” system of naming numbers, and the old British version is known as the “long scale.” In 1974 the UK officially switched from long scale to short scale, but there are still people in Britain who use the word the other way. That means that a good translator will take the time to determine the nationality of the author and the country in which the source was published before he finalizes his translation, and even then it's a good idea to see if the source document has some internal confirmation of which meaning is intended.

The word часы means a watch or a clock. It has no singular form, only plural; such nouns that lack singulars we label “pluralia tantum.” It declines likes this:

Since the word only has plural forms, the pronouns that refer to it must also by in the plural:

Since the word only occurs in the plural, you might wonder how to say “one watch.” Easy: you use the plural of the number one!

If you are talking about two, three, or four watches, then двое, трое and четверо can be used:

These collective numbers don't combine very well with the other ordinal numbers. That is, don't try to say something like:

In these circumstances it is best to add the word штука ‘unit’ to the phrase:

Some Russians allow the use of the word пара ‘pair’ in place of штука:

I say “some Russians” because to some other Russians that type of phrase sounds like просторечье “substandard speech” (see Rosenthal's commentary). If you want to be sure you sound okay, use the штука approach.

¹ Yes, yes, I know that one properly is supposed to say “no fewer than four,” but frankly “no less than four” is the way most Americans will say it nowadays, even educated ones. “No fewer than four” sounds forced and unnatural, as if someone with a mediocre education is trying to prove that he isn't ignorant.

The word нуль sometimes occurs in fixed phrases like «начать с нуля» “to start from zero,” which catches the idea of beginning a process with zero previous knowledge or experience or resources:

Just as in English you can refer to someone as being a complete zero (i.e., being a worthless human being), so also the Russian word can be used in that sense:

The word is also used to describe a certain haircut «под нуль», that is, “down to zero” or bald. It's the haircut that every draftee receives when joining the Russian army.

Как только пойдёшь в солдаты, тебя остригут под нуль.
As soon as you become a soldier, they shave you bald.

The haircut has become so popular among tough young men that sometimes they are called нули, which is probably best translated as ‘thugs.’ (You can hear the word used that way in the elusively connected song «Главное» “The important thing” by the singer Земфира.)