X-rays __________________ in 1895 by Wilhelm Conrad Roentgen, who was a German Professor.
discovered
are discovered
is discovered
were discovered
The movie Avatar _______________ by James Cameron.
is being directed
directed
was directed
is directed
How often __________ hotel carpets __________?
are / cleaned
is / cleaned
will be / cleaned
was/ cleaned
The most famous portrait in the world, Mona Lisa, ________________ by Leonardo da Vinci.
has been painted
was painted
is painted
were painted
The light bulb ____________________ by Thomas Edison.
was not invented
were not invented
has not been invented
were invented
Cars _______________ in factories.
is being produced
are produced
were produced
produced
The tunnel _________________________ at the moment, so it's closed for all traffic.
is being repaired
will be repaired
is repaired
repaired
When ___________ the Great Wall of China ____________?
is / build
built / were
was / built
were / built
The last Olympic Games _____________ in Tokyo.
are held
will be held
have been held
were held
Wooden toothpickes ______________ from birch wood.
have been cut
are cut
were cut
will be cut
Olives _______________ in Mediterranean countries.
is grown
was grown
are grown
has been grown
The Harry Potter series __________________ by J. K. Rowling.
written
wrote
is written
was written
Scissors ___________________ for cutting thin materials, such as paper and metal foil.
are used
use
used
is used
Google ____________ officially ____________ in 1998.
has been launched
is launched
were launched
was launched
Brilliant ideas ________ generally __________.
have been / copied
are / copied
is / copied
were / copied