下列说法正确的是
| A.待测液中加入氯化钡溶液有白色沉淀生成,再加稀盐酸,沉淀不消失,则待测液中一定有硫酸根离子 |
| B.用灼烧的方法可鉴别丝绸与棉布 |
| C.无色溶液中加入Na2CO3溶液产生白色沉淀,则该无色溶液中含有Ca2+ |
| D.待测液中加入AgNO3溶液,有白色沉淀生成,则待测液中含有Cl- |
If you leave the club, you will not be_____back in .
| A.received | B.admitted | C.turned | D.moved |
What I need is_____ book that contains ______ABC of oil painting.
| A.a; 不填 | B.the; 不填 | C.the; an | D.a ; the |
Jenny nearly missed the flight______ doing too much shopping.
| A.as a result of | B.on top of | C.in front of | D.in need of |
The CDs are on sale! Buy one and you get ______ completely free.
| A.other | B.others | C.one | D.ones ks |
Progress______ so far very good and we are sure that the work will be finished on time.
| A.was | B.had been | C.has been | D.will be |