背对背信用证与未经保兑的可转让信用证一样对进口商有利。（）

15.黄宗德是16世纪一位典型徽商。最初他只是经营棉布、粮食等，后获得政府许可，转而从事利润更大的食盐贸易，积累了巨额财富，用于购田置地。这说明当时（）

①农产品大量进入商品流通领域

②农本思想依然占主导地位

③政府放弃对食盐贸易的控制

④商人社会地位显著提高

A.①②

B.②③

C.②④

D.①④

Water costs money．In some places water is hard  31 ．What 32 when a town has these problems？A small town in California found a happy 33 ．

Very 34 rain ever fell there．The town had no water35 ．The water it used was 36  from a river 300 miles away．As more people  37  live in the town  38  water was needed．Now water  39  to be brought in from 600 miles away．All these cost  40 money．

The town 41 a plan．It found 42   to clean its “dirty” water．Once the cleaned water was reused  43  many ways．Five  44  lakes were built．Here people could swim and fish and go  45 ．They  46  have picnics in their new parks．Farmers had more water 47  their crops．New factories can be built，now that they have the promise of  48 ．

In most places，water is used and thrown 49．The town that saved 50 water has saved the town！

小题1:    

A．supplying

B．getting

C．to get

D．to supply小题2:    A．happens     B．happening    C is happened     D．happened

小题3:    A．key         B．answer       C answering    D．way

小题4:    

A．little

B．a little

C．few

D．a few小题5:    A．of itself   B．of its own  C．for its own    D for itself

小题6:    

A．fetch

B．take

C．brought in

D．guided小题7:    

A．come to

B．came to

C．coming to

D．came for小题8:    

A．many

B．plenty of

C．more

D．many more小题9:    

A．has

B．had

C．must

D．needed小题10:  

A．many

B．a few

C．a great many

D．a lot of小题11:  

A．put

B．made

C．supply

D．noticed小题12:  

A．a way

B．ways

C．an answer

D．a key小题13:  

A．for

B．by

C．at

D．in小题14:  

A．man-making

B．man-make

C．man-made

D．man made小题15:  

A．boating

B．to boat

C．to boating

D．on boating小题16:  

A．must

B．could

C．needed

D．had to小题17:  

A．as

B．with

C．for

D．to小题18:  

A．water enough

B．enough water

C．crops enough

D．enough crops小题19:  

A．off

B．of

C．away

D．out of小题20:  

A．it’s

B．its

C．one’s

D．his

简述主机与外设进行数据交换的几种常用方式。

卖方信贷

常用錾子有哪几种？简述各自应有场合。