对肉类产品构成情况的分析，就是对（）产量占肉类总产量的比重及变化情况的分析。 A.大

各拉杆腐蚀、磨耗深度大于（）时须更换。

A.15％

B.20％

C.25％

D.30％

Many people go to school for education. School education is very important and useful, but no one can learn everything from school. A teacher, no matter how much he knows, can't teach his student everything. His work is to show his students how to learn .He teaches them how to read and how to think. So much more is to be learned outside school by students themselves.

It’s always more important to know how to learn by oneself than to learn some facts or formulas(公式) by heart. It’s quite easy to learn some facts in history or a formula in maths, but it’s very difficult to use them. Edison and Einstein didn’t get everything from school, but they were all successful. They invented so many things. The reason for their success is that they knew how to study. They read many books outside school. They worked hard all their lives, wasting not a single moment. The most important thing is that they know how to use their brains（大脑）.

小题1:Students can’t learn everything in school because _____________.

A．the teacher doesn’t know much

B．the teacher can only teach them how to read and write

C．the teacher would not like to teach

D．there are still many things for the students to learn outside小题2:A teacher’s work is _________________

A．to teach all subjects

B．to teach everything

C．to teach the students how to read and think

D．to work hard小题3:To know how to____is much more important than facts or formulas by heart.

A．work out maths problems

B．remember all the facts

C．study science

D．study小题4:Why did the famous scientists become successful ? Because__________

A．they knew how to study

B．they remembered all the formulas

C．they didn’t get everything from school

D．they didn’t know how to use their brains小题5:Which is WRONG according  to the passage?

A．Outside school study is as important as school study

B．It’s more important to know how to learn than only remember some facts and formulas.

C．It’s very easy to use a formula in working out a maths problem.

D．It’s helpful to read more books outside school

判断疾病预后，最常用的研究方法是（）。

A.临床经验

B.疾病自然史

C.前瞻性观察

D.回顾对比

E.临床试验

士兵在利用地形地物时，要根据遮蔽物的高低、大小、形状，敌火力的威胁程度等情况，采取适当的姿势利（）用防护。

A.遮蔽界

B.危险界

C.障碍物

D.死角

房地产开发企业建造的商品房，在出售前一律不征收房产税。( )