_________(1)
A.had
B.started
C.was
D.invented

_________(2)
A.to
B.in
C.for
D.about

_________(5)
A.or
B.so
C.and
D.then

_________(6)
A.who
B.whom
C.whose
D.they

_________(8)
A.who
B.that
C.whom
D.whose

_________(10)
A.since
B.later
C.again
D.then

What does the passage primarily discuss?
A.Advantages and disadvantages of solar energy.
B.Solar energy’s advantages over other sources of energy.
C.The cost of solar energy.
D.Solar energy as an alternative for fossil fuels.

What is NOT mentioned as an advantage of solar cells?
A.They require little maintenance.
B.They are non-polluting.
C.They cost little to produce.
D.They operate quietly.

Which of the following is the main disadvantage of solar energy mentioned in the passage?
A.It is expensive.
B.Solar cells require large areas to operate.
C.It is unfriendly to the environment.
D.It depends on sunlight.

_____the salary meets my expectations, I will accept the job offer.
A.So
B.Although
C.If
D.Therefore