Ответ:

Перевод задания: Какой вариант правильный? Дополните предложения.

  1. At the moment the delegation is arriving at the station.
  2. The delegation has just arrived at the station.
  3. The delegation arrived at the station this morning.
  4. The delegation has already arrived at the station.
  5. The delegation arrived at the station two hours ago.

Present Continuous употребляется с at the moment; Present Perfect — с just и already; Past Simple — с указанием законченного времени.