At times the balance in nature is ______，resulting in a number of possibly unforeseen effects.
A．troubled B．confused C．disturbed D．puzzled
I still remember to the Famen Temple and what I saw there.
A. to take B. to be taken C. taking D. being taken
The best means to go there _________walking.
A. is B. are C. to be D. be
He is determined to become a specialist ________ computer when he grows up.
A. for B. in C. on D. about
The teacher, with 6 girls and 8 boys of her class, ________ visiting a museum when the earthquake struck.
A. was B. were C. had been D. would be
They argued ________each other _________ where to spend the golden week.
A. at; over B. with; about C. about; at D. over; on
