In Russian, to express that there is "no one" or "nothing" available for an action, we use the predicative negative pronouns некого (no one) and нечего (nothing). They are typically paired with a dative subject (the person lacking something) and an infinitive verb.
When a preposition is involved, a strict rule applies: the preposition always splits the pronoun apart. It jumps directly between the negative particle не and the pronoun, breaking one word into three separate words. In these split constructions, the vocal stress always falls heavily on не.
Splitting "Who" (кто)
Let's look at what happens to некого (no one) when a verb requires a preposition. If you need the instrumental case to say there is no one to talk with (с кем), the pronoun splits into не с кем.
| The young beekeeper had no one to talk to about bees. | Молодому пчеловоду было не с кем поговорить о пчёлах. |
Similarly, if you need the prepositional case to say there is no one to take care of (о ком), it splits into не о ком:
| The swarm left the hive, so now there is no one to take care of. | Рой покинул улей, так что теперь не о ком заботиться. |
Splitting "What" (что)
The exact same splitting rule applies to нечего (nothing). When combined with the preposition на (at) in the accusative case (на что), it splits into не на что (nothing to [look] at).
| There is nothing to look at inside the empty hive. | Внутри пустого улья не на что смотреть. |
If the bees lack materials to build from (из чего), we use the genitive case to form не из чего (nothing to [build] from):
| They had nothing to build honeycombs from, because there was no wax. | Им было не из чего строить соты, потому что воска не было. |
And if you need a container to put something into (во что), the pronoun splits into не во что (nothing to [collect] in):
| There was a lot of pollen at the apiary, but there was nothing to collect it in. | На пасеке было много пыльцы, но её было не во что собирать. |