(2013·宝鸡二检)In my brother's absence, I would like to thank all concerned on his ________.
A.behalf B.part C.business D.interest
(2013·福建毕业班质量检查)—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
(2013·安徽蚌埠一次质检)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
(2013·豫北三校联考)Friendship is both ________ source of pleasure and ________ component of good health.
A.a; a B./; / C.the; a D.a; the