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The scientist __________ the experiment for half a year, but he _______ yet.

The patent officer ______ with my file explained to me that a plant variety is not a/an _______ invention as it is a result of adjusting growth scientifically.

Exactly when the first people arrived in ________ we now know as California, no one really knows.

The dodo became extinct fairly recently so its DNA is still ________ .

Do you know the stages every inventor must ________ before they can have their invention________ .

_______ from the top of the mountain, we found the city more beautiful.

It was the building of the rail network from the west to the east coast ________ brought even larger numbers to California in the 1860s.

All efforts of cloning an animal will be ________ if there is not enough diversity in the group to overcome illness.

________ is very important in doing any scientific work.

The first thing ________ I did was to see if there were any products ________ might help me, but there only seemed to be powders ________ to kill snakes.