—Why is Peter working so hard these days?.—The _______ of failing the exam next week makes him do so.
Bats are surprisingly long-lived creatures, some _______ a life span of around 20 years.
According to the information from the airline, a small sinking part of the runway of the airport is _______ for the accident.
Obviously the measures taken by the local government have_______ the solution to drinking water problems in this region.
--Do you know when the Chinese custom_________ from? --It's hard to say. But its characteristics__________ the Tang Period.
Paper bags produced every year are ______ the world’s production of vehicles.