1) They offered tourists a free (бесплатный) sightseeing trip.

Tourists are offered a free sightseeing trip.

2) Mr Bown is dictating a letter to him secretary.

Secretary is dictated a letter by Mr Bown.

3) Mr Bailey was packing his suitcase when his wife called.

Suitcase was packed by Mr Bailey when his wife called.

4) They had signed the contract by the end of the month.

The contract was signed the end of the month.

Это было последнее задание, которое я для тебя сделала.
У тебя на странице 23 вопроса с ответами, и ни одной благодарности.