Teenagers are not allowed to stay out late _ school nights.
A. on B. in C. at D. by
lf you want to work for a magazine, we have a job for you a reporter.
A. with B. of C. as D. for
With help, we finished our work on time.
A. they B. them C. their D. theirs
There is insect on the ground. The child is very interested in it.
A．a B./ C．the D．an
People have learned a lot from
studies．
A. science B. scientific
C. scientist D. sightseeing
The computer was invented in the 20th
A. sentence B. center
C. concert D. century
