第三部分：阅读理解（共20小题;每小题2分, 满分40分）
阅读下列短文，从每篇短文后所给各题的四个选项（A、B、C和D）中，选出最佳选项，并在答题卡上将该项涂黑。
MEXICO CITY： A jetliner from the beach resort of Cancun was briefly hijacked as it landed in Mexico City on Wednesday. The hijackers released all passengers shortly before federal police stormed the plane, and the crew emerged unharmed moments later.
Police, who did not fire a single shot, led as many as eight handcuffed men away from the airplane, which was isolated at the end of a runway in an area designed for emergencies. The hijackers’ motive was unclear, though Mexican news media initially identified them as Bolivians demanding to speak with Mexican President Felipe Calderon.
US, French and Mexican citizens were among the 112 passengers and crew on Aeromexico Flight 576, according to a US official who had been briefed on the situation. The official was not authorized to discuss the case and spoke on condition of anonymity.
Mexico’s transportation and communications secretary, Juan Molinar, said there was no bomb on the airplane, although some passengers said one of the hijackers held a package that resembled an explosive device, and a bomb squad (拆弹小组) was later seen near the airplane.
He did not immediately identify the hijackers or speculate on their motive.
“Various people who participated in the act have been detained and we are investigating,”Molinar said.
The attorney general’s office said it was opening an investigation into terrorism and kidnapping but did not specify how many people could be charged.
Mexican news media initially reported the hijackers were Bolivian, but Bolivia’s ambassador to Mexico, Jorge Mancilla, said Mexican authorities had no evidence that was the case. Mancilla said sources told him they could be Colombian or Venezuelan. Several passengers told reporters they did not notice a non-Mexican accent.
Passenger Rocio Garcia told the Televisa network that the pilot made an announcement after landing in Mexico City that the airplane was being hijacked. Passengers said the hijackers never communicated with them directly.
“These were scary moments,”she said.
She said she saw one of the hijackers whom she described as a well-dressed, older man.
“He looked fine, like a normal passenger,”she said.
Passenger Daniel Hernandez said he saw a hijacker carrying a Bible.
51．From the first paragraph we can conclude that _________.
A．the hijackers just wanted to play a trick on the police
B．the hijackers didn’t prepare for their action
C．the hijackers surrendered before the police fired
D．the hijackers lost their way at the last moment
52．From what Juan Molinar said we can learn that _________.
A．police were still trying to identify a possible bomb
B．passengers succeeded in stopping the explosion
C．a frightening bomb was found later on the airplane
D．several Mexicans were involved in the hijacking
53．What may be the first step taken when the hijacked plane landed?
A．They gave a sudden attack at the hijackers.
B．They kept the plane away from other planes.
C．They asked the crew to control the hijackers.
D．They abandoned the plane at the end of the runway.
54．The hijackers, as some passengers described, _________.
A．were good at bargaining with the police       
B．were all well-dressed American old men
C．all came from Colombia or Venezuela          
D．stayed calm and appeared noble, educated