________he is pleased with his success, Robert wonders what will happen to his private life

When did you meet your English teacher— While I _________ a bike along Jiaomen River.

The old man said the accident happened ________ careless driving,so a large sum of money ________ be paid by the driver.[ ]

ys mobile internet devices are pushing up demands for online education, which makes people see it as one of the most____ new market.

Kate is one of the________ customers to Meet Allbecause she lives just two blocks away.