What are these people famous for? Use the article where necessary.

1) Grigory Oster is _ popular children's writer. _Children and adults like
his books of funny advice.
2) Svyatoslav Fedorov was___wonderful eye doctor, he treated___serious eye diseases.
3) Yuri Bashmet is ___famous musician. His concerts take place in ___best concert halls.
4) Sergei Korolev was __ great engineer and __ scientist. His ideas are still very important for__space engineers.
5) Ilya Repin was __ great Russian painter. You can see his best works at the Tretyakov Gallery.
6) Georgy Grechko is_cosmonaut; he has flown to_space three times.
7) Ulyana Lopatkina is_famous ballet dancer; she dances at the Mariinsky
Theatre in St Petersburg.
8) Peter_Great became_Tsar when he was_young boy.
9) Ippolit Romanov was_inventor. In 1899 he invented an electric car.
10) Vladimir Putin became_president in 2000. He was_ President of
the Russian Federation from 2000 to 2008.
11) Faddei Bellingshausen and Mikhail Lazarev were_explorers; they
discovered Antarctica in 1820.