阅读理解。
Three types of pangolins (穿山甲) exist in Africa - the giant pangolin, the tree pangolin and the most
widespread, the ground pangolin. Pangolins have small heads and long, broad tails. They are toothless and
have no external ears, although their hearing is good. Their sense of smell is well-developed, but their sight
is poor. The weight of the scales (鳞片) and skin make up about 20% of their weight.
The common pangolin prefers sandy soils and is found in woodlands and savannas (热带草原), within
reach of water.
All pangolins can roll themselves into a ball to defend themselves. The cutting action of their scales protects
them too. Pangolins also have scent glands (臭腺) that release strong, foul smelling secretions. Pangolins are
normally alone. Females are usually alone with their young. The young are 6 inches long and weigh 12 ounces
at birth. Their pale, soft scales begin to harden by the second day. The baby is folded in the mother's lap or
rolled-up body. It is nursed for 3 to 4 months and begins to eat termites (白蚁) at 1 month. At this time the
infant begins to accompany the mother, perhaps riding on the base of her tail. If the mother senses danger the
baby slips under her and is protected when she rolls up her body.
Pangolins use their sense of smell to locate termite and ant nests. They dig up the insects with their claws
and use their extremely long tongues to eat them.
1. When pangolins are ____, they release strong, foul smelling secretions.
A. happy
B. sad
C. frightened
D. angry
2. Which of the following words best describes the function of the pangolin's scales?
A. Heavy.
B. Beautiful.
C. Protective.
D. Hard.
3. When does the infant begin to accompany the mother pangolin?
A. At l month old.
B. At 2 months old.
C. At 2-3 months old.
D. At 3-4 months old.
4. What does the last paragraph mainly talk about?
A. The pangolin's habitat.
B. The pangolin's diet.
C. The pangolin's behavior.
D. The pangolin's appearance.
式中，C表示订货成本；D表示月需求量；K表示库存持有成本。
。