During a trip to observe wild animals in Africa, I encountered the least brave animal on earth, the wildebeest (角马). I sat on a riverbank for three hours watching a group of thousands build（1） the courage to drink water.More than a million wildebeests（2）northward into the wetlands. It is a long, dry and difficult journey. Frequently, the only available water is the Grumeti River,（3）represents both life and death. Unlike some creatures that can take moisture（4）the grass they eat, wildebeests must drink from the river to live. The river supports other wildlife, including（5）that kill and eat other animals. Though thirsty（6）traveling, the wildebeests stand back from the water, sensing possible danger.Moving slowly toward the bank can（7）hours, as an individual wildebeest steps forward, steps back and then carefully steps forward again. More wildebeests gather together and advance, gradually pushing the leaders to the river,（8）they want to go or not. It’s been a long time（9）they drink last time, and you feel their anxiety for water.Lions are possibly on the（10）, saving energy as they wait for an opportunity for lunch. Once the large group moves to the river, lions could（11）, making the group running in a wild and uncontrolled（12）. The mad rush would raise a dust cloud that blocks the（13）of the wildebeests nearby. A kill is almost guaranteed.Sitting on that riverbank, I noticed that a young wildebeest finally stepped ahead and drank while the（14）adults held back. Soon, others began drinking. But（15）lining up along the bank, taking turns, they gathered and pushed. Some had to walk farther into the water than they were （16）to go. Those pushed farther in water got frightened and in（17）frightened the others. They all retreated hastily and returned to their route. Only the few that were（18）enough got a drink. The others went（19）. There was no danger that day. Only the wildebeests’ fear and（20）of courage kept them from drinking.

A.up B.out C.in D.over
问题2：
A.visit B.travel C.see D.swim
问题3：
A.that B.which C.where D.when
问题4：
A.above B.under C.from D.over
问题5：
A.this B.those C.that D.them
问题6：
A.among B.above C.from D.between
问题7：
A.take B.pay C.spend D.charge
问题8：
A.when B.where C.what D.whether
问题9：
A.before B.because C.since D.though
问题10：
A.watch B.sight C.shout D.walk
问题11：
A.rescue B.join C.attack D.visit
问题12：
A.solution B.way C.method D.role
问题13：
A.fear B.shout C.jump D.view
问题14：
A.fearful B.confident C.pleasant D.happy
问题15：
A.regardless of B.instead of C.in case of D.in spite of
问题16：
A.interesting B.pleasant C.willing D.reluctant
问题17：
A.hope B.story C.step D.turn
问题18：
A.short B.bold C.kind D.small
问题19：
A.thirst B.hunger C.thirsty D.hungry
问题20：
A.show B.grasp C.look D.lack