Intended Duration
In Russian, when you want to express how long an action, stay, or state is intended or planned to last, use the preposition на followed by the accusative case.
Notice how feminine time words change to their accusative forms (for example, неделя becomes неделю), while masculine inanimate nouns (like месяц or день) remain unchanged from their dictionary form.
Renting and Leasing
This grammar pattern is extremely common when dealing with accommodation and real estate. To say you are renting an apartment or a room, use the verb снять.
For more formal, commercial, or long-term leasing, use the noun аренда (lease/rent) and the verb арендовать (to lease).
Rentals and Lending
The vocabulary changes slightly for movable objects like cars, bicycles, or equipment. To rent these items, you say you take them "into rental" (в прокат).
If you are lending or borrowing something, use the verb одолжить. The timeframe for how long the item or money is lent still uses на + accusative.
Stays, Trips, and Extensions
This intended duration structure is the standard way to talk about travel itineraries. If you are staying at a hotel or with a friend, use the verb остановиться.
You can also use this construction to describe the planned length of events, such as a business trip (командировка), a visit (визит), or a university semester (семестр).
Finally, if plans change and you need to extend your time, use the verb продлить (to extend). Here, the preposition на indicates the additional amount of time being added to your original plan.