Uzupełnij zdania odpowiednią formą czasownika 'to be' (was/wasn't/were/weren't) oraz prawidłową formą czasownika z nawiasu.

1. The first computer … (invent) by Charles Babbage in the early 19th century.

2. The first electronic digital computer … (build) in 1943 in Britain. It … (call) ‘Colossus’ and it … (use) for decoding enemy messages in the war.

3. Businesses began to use computers in the 1950s, but computers … (not sell) in shops until the early 1970s.

4. The first desktops computers … (develop) in the late 1970s.

5. Internet access via a modem … (add) in the 1990s, but wireless access … (not add) to most computers until about 2000.