Choose the best word/phrase to complete the sentences from 10 to 30.
Many teenagers show signs of anxiety and _______ when being asked about their future.
A.depressed
B.depressing
C.depression
D.depress

An economic _______ is a time when there is very little economic activity, which causes a lot of unemployment and poverty.
A.depression
B.development
C.mission
D.improvement

Someone who is _______ is hopeful about the future or the success of something in particular.
A.pessimistic
B.stagnant
C.optimistic
D.powerful

Can you make a ________ estimate of how much our expedition in the desert may be?
A.roughly
B.roughing
C.roughen
D.rough

More and more ________ are very excited at discovering as many interesting things in the deserts as possible.
A.explorers
B.explorations
C.exploratory
D.explores

You can see the details_________the computer screen.
A.in
B.at
C.on
D.by

Don't walk too fast. I can't keep_________
A.up with
B.on with
C.on to
D.up to

The Sahara contains complex linear dunes that are ________ by almost 6 kilometers.
A.located
B.developed
C.lay
D.separated

The Simpson Desert was named _______ Mr. Simpson, President of the South Australian Branch of the Royal Geographical Society of Australia.
A.with
B.for
C.at
D.after

Nobody knew that Uncle Ben was coming to see us. He arrived______.
A.expectantly
B.unexpecting
C.unexpectedly
D.unexpected