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Unprecedented Aviation Mystery
A Boeing 777 took off from Malaysia’s largest city of Kuala Lumpur at 0:41 am on March 8.
_____destination was Beijing. But the flight never arrived, ______ （leave） friends and relatives of the passengers onboard weeping and worrying.
There were 239 people____   board the Malaysia Airlines flight，including China， Vietnam，the US，Singapore， and the Philippines _______ still ______ （search）for the missing plane.
Its __________ （disappear）is an "unprecedented（史无前例的）aviation mystery”， Azharuddin Abdul Rahmanm，head of Malaysia’s Civil Aviation Authority，said on March 10.
There was no sign of ____   crash.
About two hours of after taking off，air traffic control suddenly lost contact with the plane. The weather was clear，the pilots didn't make any distress calls，       no debris 碎片） was found in the area ______ the flight last made contact.
Besides，airplane crashes________ （typical）occur during takeoff or landing. Only 9 percent of fatal accidents happen ______ a plane is at cruising（平稳行进的）altitude，according to a report by Boeing in August.