Сделать предложения отрицательными 1) The construction of Moscow - Peterburg line began in 1843 2) The students were

1. The construction of Moscow - Peterburg line began in 1843. - The construction of Moskow - Peterburg line didn\'t begin in 1843. - Строительство линии Москва- Питербург (не) началось в 1843 году. 2. The students were testing new devices in the labolatory last evening. - The students were not testing new devices in the laboratory last evening. - Студенты (не) тестировали новые приборы в лаборатории вчера вечером.