I want to know the answer to the following question:
What happened to some expressions in Pushkin's writing?
All the background I'm provided with is that "In fact, many expressions used by Russian writers of the early 19th century, in particular Pushkin, Mikhail Lermontov (Михаи́л Ле́рмонтов), Nikolai Gogol (Никола́й Го́голь), Aleksander Griboyedov (Алекса́ндр Грибое́дов), became proverbs or sayings which can be frequently found even in modern Russian colloquial speech.". Is that enough to answer the question?
Answer: yes