Три девочки — Тася, Оля и Алена — собирали черную и красную смородину. Известно, что две девочки из трех собирали черную смородину. Алена и Тася собирали одинаковые ягоды.

1) how many lines does the tube have?
2)where can you see red double-decker buses?
3) what are black cabs?

1. Has the Tube 12 lines? .The Tube has 12 lines, hasn't it? .The Tube has 12 or 11 lines? What has 12 lines? How many lines has the Tube?
2. Can you see red double-decker buses in London? You can see red double-decker buses in London, can't you? Can you see red double-decker buses in London or in Paris? Where can you see red double-decker buses? What can you  see in London?
3. Are black cabs special taxis? Black cabs are special taxis, aren't they? Are black or yellow  cabs special taxis? What colour are special taxes? What are black cabs?