Prevented (A) the soil from (B) erosion, trees are of great importance (C) when floods hit mountainous areas (D).
A.Prevented (A)
B.from (B)
C.of great importance (C)
D.mountainous areas (D)

Perfume (A) tends to be lost (B) its flavor when (C) it has not been properly sealed (D).
A.Perfume (A)
B.tends to be lost (B)
C.when (C)
D.has not been properly sealed (D)

With the dawn of space exploration, the notion that atmospheric conditions on Earth may be unique in the solar system was strengthened.
A.outcome
B.continuation
C.beginning
D.expansion

Let's wait here for her; I'm sure she'll turn up before long.
A.arrive
B.return
C.enter
D.visit

This tapestry has a very complicated pattern.
A.obsolete
B.intricate
C.ultimate
D.appropriate

During the Great Depression, there were many wanderers who traveled on the railroads and camped along the tracks.
A.veterans
B.tyros
C.vagabonds
D.zealots

We decided to pay for the furniture on the installment plan.
A.monthly payment
B.cash and carry
C.credit card
D.piece by piece

I could see the finish line and thought I was home and dry.
A.hopeless
B.hopeful
C.successful
D.unsuccessful

Carpets from countries such as Persia and Afghanistan often fetch high prices in the United States.
A.Artifacts
B.Pottery
C.Rugs
D.Textiles

Though many scientific breakthroughs have resulted from mishaps,it has taken brilliant thinkers to recognize their potential.
A.accidents
B.misunderstandings
C.incidentals
D.misfortunes