Solution:
Here are the completed sentences with the correct articles:
- Mikhail Lomonosov, a great Russian scientist was born in the north of Russia.
- An outstanding Russian poet Pushkin was born in Moscow.
- Nikolai Nekrasov, a great Russian poet was born near Yaroslavl.
- William Shakespeare, a well-known English writer was born in Stratford-upon-Avon.
- Jack London, a famous American writer travelled a lot.
Answer: a, the, An, a, a.