The preposition в (or во) is used with the accusative and prepositional cases. Unfortunately for beginners, there is no reliable way of determining when to use either в, or во and it may take some time to develop an intuitive ability to combine either preposition with other words as a native would. However, there are some guidelines and theories in existence and the preposition во is generally used:
a. Before a monosyllabic word beginning with an awkward cluster of consonants.
For example:
Some people ascribe meaning to symbols in dreams. – Некоторые люди приписывают значение символам во сне.
He had a ball in [the / his] mouth. – У него был мяч во рту
However:
He spent a lot of time in the area in the days before her disappearance. – Он провел много времени в этом районе в дни перед её исчезновением.
b. If the following word begins with the letter в .
For example:
The people who live there are at the mercy of nature. – Люди, которые там
живут, находятся во власти природы.
He’ll do anything to keep himself in power. – Он сделает все, чтобы
удержать себя во власти.
However:
A van hit the gate. – Минивен врезался в ворота.
The ball flew into the goal and goalkeeper caught it. – Мяч летел в ворота
и вратарь его поймал.
I am going down to the lake on Sunday afternoon. – Я иду к озеру в воскресенье днем.
During the time of the war, many people were displaced. – Во время войны многие люди были вынуждены покинуть свои дома.
c. If the following word contains a cluster of consonants including the letter в .
There are butterflies in the garden. – Во дворе есть бабочки.
d. In certain expressions of long–use.
For example:
A hundredfold; a hundred times – Во сто крат
It will be a hundred times worse. – Будет во сто крат хуже.
The department will be [headed / led] by the new director. – В отделе будет во главе новый руководитель.
To [be in / get into] hot water (with somebody) – Попасть как кур во щи
посл
e.
Before an initial vowel.
For example:
I will speak to her tomorrow in order to avoid any confusion. – Я поговорю с ней завтра, во избежание путаницы.
The contract has been amended in accordance with the guidelines. – В контракт были внесены изменения во исполнение с руководящими принципами.
I came here on behalf of my son. – Я пришла во имя моего сына.
There are sacrifices you have to make in the name of love. – Приходится чем–то жертвовать во имя любви.
Some words can be used with both variants.
For example:
Hopefully they will turn it into something else someday. – Надеюсь, когда–нибудь они превратят это [в / во] что–нибудь другое.
Some theorists argue that both в and во may be used with the prepositional case, whilst во is required when the preposition is used in a locative sense (that is, when it refers to a location). Although appealing given its simplicity, there are exceptions, which makes it difficult to regard this as a rule.
For example:
I live in Spain. – Я живу в Испании.
Another approach is to simply choose whichever version allows you to combine the preposition with a word as seamlessly as possible.
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