According to the passage, what kind of signal has long periods of light that are regularly broken by two or more periods of darkness?
A.Flashing
B.occulting
C.Group occulting
D.Group flashing

Which of the following is NOT mentioned in the passage as one of the functions of lighthouses?
A.To notify sailors that bad weather is approaching
B.To indicate that land is near
C.To warn of danger from rocks and reefs
D.To help sailors determine their location

He doesn't seem to be successful ____hard he works.
A.whatever
B.but
C.however
D.although

We've decided to interview only ten ___ for the job .
A.appliances
B.applicable
C.applicants
D.applications

Is there somewhere I can _______ this jumper?
A.look over
B.try out
C.try on
D.look out

- "How do you like your steak done?"
- "_______________ "
A.Just a little
B.Yes, I do
C.Not much
D.Well done

According to the passage, which of the following is TRUE about solar power ?
A.It is 6,000 times more powerful than energy from fossil fuels.
B.There is very little of it available in Iceland.
C.There is enough of it to far exceed the energy needs of the world.
D.It is being used in 100, 000 private homes worldwide.

According to the passage, why should we consider using alternative energy sources ?
A.Because conventional energy resources are being depleted, and they cause environmental damage.
B.Because global warming has increased the amount of sunlight that reaches the earth.
C.Because they are free and available worldwide.
D.Because fossil fuels are no longer available.

Where is the best place in the passage to insert the following sentence:
" Although the US is not utilizing geothermal resources to this extent, the Western US has a similar capacity to generate geothermal power"
A.after the phrase " global scale"
B.after the phrase " by geothermal power"
C.after the phrase " earth-friendly"
D.after the phrase " growing steadily"

______(61)
A.others
B.The other
C.The others
D.other