So far as I know, more than one person _______ connected with the accident.
A. is
B. has
C. are
D. have
Every possible means _______ tried, but without much result.
A. has been
B. have been
C. are
D. is
With the company facing a serious financial situation this year, the staff ______ clearly worried about the news of job loses.
A. is
B. are
C. were
D. was
The worker and poet ______ to the party the other day.
A. is invited
B. was invited
C. has invited
D. invited