1 Complete the sentences with the correct form of the verb in brackets.
1 Liquid Paper was _______________ (invent) by Bessie Nesmith in 1951.
2 Penicillin was _______________ (discover) by Alexander Fleming.
3 The first telegraph system was _______________ (build) by Samuel Morse in 1835.
4 The first radio transmission across the Atlantic was _______________ (make) on December 12, 1901.
5 The World Wide Web was _______________ (launch) in 1990 after Tim Berners-Lee created the first browser.
6 The first commercial mobile phones were _______________ (sell) by NTT in Japan in 1979.