They will take the the total number of countries in the EU to 27, and play a full part in the bloc's decision-making, in the Commission, the Council and the European Parliament.

But do you know the first thing about them?

Find out by taking our quiz, with 10 questions on history, sport, culture and wildlife.

Question 1

When Romania joins the EU, the bloc�s population of one of the following species will roughly double. Which?

A: Vampire bats B: Brown bears C: Wolverines

Question 2

Which of the following delicacies will be found living wild in the EU once Bulgaria and Romania join?

A: Beluga sturgeon B: Tiger prawn C: Yellowtail amberjack

Question 3

In 1986 Steaua Bucuresti Football Club became the first Eastern European team to win the European Cup by beating Barcelona in dramatic fashion. How did they do it?

A: By scoring two goals in the last minute of play B: By hanging on to a 1-0 advantage, despite having three men sent off C: By saving all of Barcelona�s penalties in a shootout

Question 4

In what sport does Bulgarian Kaloyan Mahlyanov rank among the best in the world?

A: Sumo wrestling B: Golf C: Javelin

Question 5

Where does Romania take its name from?

A: An ancient Balkan ruler, King Rom B: The Romans, who conquered the region in about AD100 C: The Roma (gipsy) people and their language, Romani

Question 6

Where does the Bulgarian capital, Sofia, take its name from?

A: An ancient Bulgarian ruler, Queen Sofia B: A church dedicated to Saint Sophia C: A medieval university dedicated to wisdom (sophia in Greek)

Question 7

Which of the following are Bulgarians credited with inventing:

A: Yoghurt B: Rice pudding C: Trifle

Question 8

"I was in tears. I had to go out. The girl is wonderful. She can do anything!" The conductor Sir Georg Solti (1912-1997) was talking of which Balkan soprano?

A: Ileana Cotrubas B: Angela Gheorghiu C: Anna Tomowa-Sintow

Question 9

What did Bulgaria offer to supply to Greece when the 2004 Olympics put strains on domestic production?

A: Bread B: Wine C: Electricity

Question 10

What was Bulgaria and Romania�s biggest export to the EU in 2005?

A: Clothing B: Wood C: Electrical machinery

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