In my brother's absence, I would like to thank all concerned on his ________.
A.behalf B.part C.business D.interest
—What does PM 2.5 mean?
—It's a professional ________ indicating the condition of air pollution.
A.term B.item C.number D.mark
It is no ________ pretending you did not know because everyone saw the whole accident.
A.use B.help C.time D.joke
—He has a lot of friends who have a lot in ________ common with himself.
—Indeed.Birds of ________ feather flock together.
A.the; / B.the; a C./; a D.a; the
Finding information in today's world is easy.The ________ is how you can tell if the information you get is useful or not.
A.knowledge B.ability
C.competition D.challenge
Friendship is both ________ source of pleasure and ________ component of good health.
A.a; a B./; / C.the; a D.a; the