四、完形填空
When you are in a boat far out at sea, suddenly, you hear a loud, deep, and beautiful song. Just as you are starting to enjoy it, the song ends. Then, it
starts
1
again. Who is out there making such music?
It sounds like the music that people make.
But
2
the music is in fact made by some whales (鲸). Scientists say some whales
express
3
their loneliness through these songs. They may even sing the songs to show their
sadness
4
over the loss (失去) of a loved one.

Each of these whale songs can
last
5
from a few minutes to half an hour. The singing can go on for hours, or even days. It is very loud, and can be heard far away. What is more
amazing
6
is that whales from the same social (社交) group sing the same song at the same time. Whales from different social groups sing different songs even when they are
together
7
. The music may change over time, but whales from the same group
always
8
sing the same songs. Studies show that this helps the whales to exchange important information with one another in the group.
Scientists have been studying whale songs for a long time, but they still
wonder
9
why whales sing. They haven't found out the meanings of these songs. But maybe this is not a bad thing, because the
beauty
10
of nature often lies in its mystery (神秘). And the mystery could be part of the reason (理由) why the song sounds so beautiful to the human ear.
(
B
) 1. A. misses
B. starts
C. grows
D. leaves
(
C
) 2. A. If
B. So
C. But
D. Till
(
C
) 3. A. remember
B. forget
C. express
D. check
(
D
) 4. A. joy
B. happiness
C. interest
D. sadness
(
A
) 5. A. last
B. repair
C. stop
D. cheer
(
A
) 6. A. amazing
B. tiring
C. relaxing
D. worrying
(
B
) 7. A. off
B. together
C. out
D. away
(
D
) 8. A. never
B. seldom
C. sometimes
D. always
(
C
) 9. A. think
B. know
C. wonder
D. dream
(
D
)10. A. fashion
B. trick
C. change
D. beauty
Exercise 5 of Unit 5 of 7B Pronunciation & Integration ( [ )