The riddles are simple, so I won't say how many letters to use =Ъ
1. ...he raised his eyes to a large black card with gold letters hanging to the side of the wide door, glazed with wavy and pink glass. He quickly figured out the first three letters: "Pa-re-o - Pro." But then came a plump, double-sided thing, the meaning of which was unknown. "Could it be 'proletarian'?" thought Sharik in surprise, "that can't be."
2. Japanese, scissors, paper
3. crumb-rinsing
4. even-toed ungulate, a box with who-knows-what, an outboard motor (!), a missing element
5. drank - quickly - corpse
6. tease, kiss, talk