---- How did it __________ that you made such a silly mistake?
---- I myself haven’t figured it out yet.
A. come up B. come about
C. come across D. come on
The water in the river isn’t fit to drink, for you know, it __________.
A. was polluted B. was polluting
C. had been polluted D. has been polluted
I hear Mr. Smith was writing a story last year and he still__________.
A. do B. does C. is D. am
I haven’t seen _________ Maggie since I came here.
A. as lovely a girl as B. so a lovely girl as
C. girl as lovely as D. as a lovely girl as
He is rather difficult to make friends with, but his friendship, ________, is more true than any other.
A. after gaining B. while gaining
C. once to gain D. once gained
Many people can’t learn any lessons from the mistakes they’ve made __________ they get hurt somehow.
A. whether B. unless C. if D. as
