The lack of eco-friendly habits among the public is thought to be a major _____of global climate change.
______ the police thought he was the most likely one, since they had no exact proof about it, they could not arrest him.
My best friend, Tom, should ______ me ______ to my boss, which hurt me deeply.
Samuel Clemens, _______ as Mark Twain, was one of the most famous American writer.
After several part-time jobs, he has now got a ________ job in a bank.
—Jackson had a car accident.— He _______ have drunk so much and driven.