Переход от активного залога к пассивному: 1) The workes had constructed the first metro line by May 1935. 2) The first line connected two districts. 3) Moscow metro builders did the construction work in difficult geological conditions. 4) During the Great Patriotic War the metro builders continued the work. 5) The belt line links 18 districts of the capital. 6) An automatic driver conducts trains according to the schedule. 7) Before holidays Muscovites decorate the streets of the city with flags, portraits, flowers and garlands of coloured bulbs. 8) An automatic driver has undergone successful tests.

Не спец в английском. Я бы так выполнил это задание.

1) T he first metro line had been constructed (by workers) by May 1935

2) T wo districts were connected with t he first line

3) T he construction work was done (by Moscow metro builders) in difficult geological conditions

4) The work was continued During the Great Patriotic War

5) 18 districts of the capital are linked with t he belt line

6) Trains are conducted with a n automatic driver according to the schedule

7) T he streets of the city are decorated with flags, portraits, flowers and garlands of coloured bulbs b efore holidays

8) An automatic driver was successfully tested

(В последнем предложении не буквальный переход, а по смыслу. "has undergone" - само по себе с пассивным значением, хотя формально это активный залог. Это ощущается и в русском языке: автопилот (автомашинист) подвергся успешно испытаниям (прошел успешно испытания). Поэтому формальное обращение будет выглядеть странно: Successful tests have been undergone with an automatic driver)