Ответ:

  1. The catch goes round the sun.
  2. Does — Mark speak — Spanish?
  3. Pushkin is an outstanding Russian poet.
  4. The 22nd of December is the shortest day in the year.
  5. Dad often says that Mom is his better half.
  6. — Isn’t it warm today, is it? — No, it was warmer yesterday.

Ответ: 1) the; 2) —, —; 3) an; 4) shortest; 5) better; 6) warmer.