17. Be when you cross the road.
–Why do you look so upset? –The electricity was cut off suddenly and my essay _______ unfinished since.
– It is said that Frank is very rich and is always changing his private cars .What is he?–_______ of a manager, I am not sure.
Among so many people at the party, I _______ John, one of my classmates after 20 years.
He was about to leave the office for home _______someone knocked the door and asked for some help.
There are nearly one hundred foreign students in our university, most of _______ are from America and Australia.