Răspuns:
1.They hadn't talked over the phone before 1876.
2.They hadn't used electric light bulbs before 1860.
3.They hadn't traveled to space before 1961.
4.they hadn't listened to the radio before 1924.
5.They hadn't watched TV before 1926.
6.They hadn't played computer games before 1981.
7.They hadn't drove cars before 1895.