Around the world， 300 million tons of plastic ________ each year， of which about 10 percent ends up in the sea． （ ）
A．is createdB．was created
C．creates
The watch _______ you gave me keeps perfect time．（ ）
A．whoB．whatC．that
She went to a European university to study art．_______ university is really amazing．（ ）
A．AnB．TheC．A
He ________ in Zhuzhou since seven years ago．（ ）
A．worksB．workedC．has worked
The passengers _______ show their ID cards before getting on the plane．（ ）
A．mightB．mustC．could
Her birthday is ______ winter，the most beautiful season in a year．（ ）
A．inB．atC．on