A study of more than five million books, both fiction and non-fiction, has found a marked decline in the use of emotional words over time．The researchers form the University of Brist
---- Excuse me sir, where is Room 301? ---- Just a minute. I’ll have Bob ______ you to your room. A. show B. shows C. to show D. showing
是重要的核工业原料，它的浓缩一直被国际社会关注，有关说法正确的是 A、原子核中含有92个中子 B、原子核外有143个电子 C、和互为同位
在水溶液中能大量共存的一组是 A．0. 1 mol · L−1的NaOH溶液中：K+、Na+、SO42-、CO32- B．K+、Cu2+、OH−、NO3- C．0.1 mol · L−1的 Na2CO3溶液：K+、Ba2+、NO3-、Cl−
---Is that your book? ---Yes, ________. A. it is B. it isn’t C. it’s D. he is
一Shall we go out for a walk?一I’m afraid not．We can’t go out_____our work is being done． A．before B．until C．as D．after
下列物质在氧气中燃烧时，集气瓶内需要预先加入少量水或细沙的是（ ） A．硫磺 B．铁丝 C．木炭 D．红磷
已知：△ABC的三边长a、b、c满足a＋b＋c－2－4＋3＝0．求△ABC的周长．
2分
4分
原不等式组的解集为
6分