从程序上说，大型活动策划和实施，要先后完全按照公关四步工作法的要求执行（） A.立项

慢性风湿性心脏瓣膜病常见致死原因为（）

A.脑栓塞

B.心力衰竭

C.心律失常

D.心源性休克

E.肾衰竭

水分和无机盐是通过茎的哪部分运输的？某同学就这个问题进行了如下探究：

作出假设：水分和无机盐是通过茎的木质部运输的．

制定和实施探究方案：①取一段柳的枝条，将其下部处理成只有木质部后，插入装有土壤浸出液（无色透明，其成分为水和溶解在水中的无机盐）的广口瓶中；②观察并记录实验现象．

请分析回答下列问题：

（1）该同学作出假设的依据是：茎的木质部中有______，是上下相连通的．

（2）该实验必须用带叶的枝条，原因是要通过叶片的______来促进水分和无机盐的运输．

（3）将柳的枝条下部处理成只有木质部的目的是排除茎的______的干扰．

（4）为了能够在茎的横切面上或纵切面上观察到溶液的位置，需要将该同学方案中无色透明的土壤浸出液改为______来做实验．

I will teach you everything you need to know on How To Repair Your Sewing Machine Admittedly, the book is mainly about sewing machines with just four of the 70 pages, including the copy clear, sharp pictures of many different sewing machines, cleaning, and timing, etc., so there is no need to turn pages back and forth in order to find the picture that goes with the text. It’s clear, and it’s simple instructions to teach you How To Repair Your Sewing Machine.

I will teach you how to thread all the different styles of sewing machines, plus winding the bobbin and selecting the correct needle.

I will show you how to properly clean all the different sewing machines, plus how to check the virious parts for wear and breakage. I will show you how to check for problems such as noisiness,thread breakage, needle breakage,etc.

I will show you how to straighten the needle and presser（压脚杆）bars and level the presser foot on all sewing machines.

I will show you how to check motors, lights, controls and wiring（线路）for various problems. I will show you how to properly time the needle bar, the hoor or shuttle, etc., so the sewing machine will sew perfectly on all tyes of material and satisfy customers.

I will show you how to set the tensions on all the different sewing machines by having an actual gauge（计量器）to use in this setting.

And I will show you where to purchase wholesale parts and new sewing machines, including where industrial machines can be purchased wholesale.   

1.The purpose of the writer is to      .

A.teach you how to repair your sewing machine

B.draw your attention to his book

C.show you where to repair your sewing your machine

D.show off his advantage over others

2.The underlined word in the third paragraph means ______.

A.use      B.part     C.breaking      D.repair

3.In order to get a picture matching the text, you      .

A.have to turn over the book      B.don’t have to turn over the book

C.should read the whole book carefully       D.need read the tips as follows

4.If you want to buy a lot of industrial machines, you can     .

A.tell the writer of the book  B.order them directly from the factory

C.find the detailed information in the book  D.order according to the picture

The man who thought of ________a gas engine with wheels was the inventor of the automobiles.[ ]

A. comparing 

B. combining

C. competing  

D. connecting

阿根廷总统庇隆的第二任妻子有“阿根廷玫瑰”的美誉。