---What’s your impression of the Great Wall?---Wonderful! Once ____ , it can never be forgotten.
The girl’s sudden death _____ the police’s _____ this matter.
With the crop’s production _____ rapidly, food price is _____ year by year.
We don’t doubt _____ he can do a good job.
On his way to school, he was _____.
The woman _____ there, _____ in a blue shirt, is Lily’s teacher.