下列的数据库管理系统属于网状模型的是()。A．1MS数据库管理系统 B．CODASY

根据短文内容，从短文后的七个选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

How to Make a Glodfish Live for Decades

Believe it or not , a goldfish could live for 10—25 years ot longer if it’s given proper care .However , with normal care it usually lives for about 6 years . The Guinness Book of World Records mentions a goldfish named Tish that lived 43 years! ____小题1:__.

Purchase the largest possible tank you can . While using a 20 liter tank is better for the fish than any kind of a fish bowl , at least 40 liters is necessary for quality of life a single fish . Chinese a tank with large surface area to increase the amount of oxygen in contact with the surface of the water.

__小题2:      Be sure that any decorations you choose aren’t hollow (harmful bacteria can grow inside ) and that they don’t have sharp edges . Provide your fish with different areas in the tank , such as an open area ideal for swimming and a hiding area . If you feed them at the same time every day , they will soon be waiting for you at that time and grow used to your presence .

Add some equipment to increase oxygen into the water . __小题3:     You can also have the current from a “waterfall” type filter help agitate (搅动) the water ‘s surface .

Clean the tank at least once every two weeks , but more frequently is preferable due to the large amount of waste . __小题4:     

Feed the goldfish one to three times daily with food apecifically designed for goldfish . ___小题5: Give them only as much as they can eat in a few minutes , and clean any leftovers immediately.

A.Provide mental and physical stimulation (刺激) for the fish .

B.Be aware that goldfish will not eat below 50--55  °C (10--14°C).

C.Here’s how to help your commpanion survive into the “ golden years ”.

D.If you do need to catch your fish ,consider using a plastic container rather than a net .

E.A small air pump can be necessary .

F.How often you do this will depend on the size of you tank , the number of fish .

G.If you choose to feed them more often , then reduce the size of the meals so you don’t overfeed.

在窗体上有几个对象，运行程序时，当对象得到焦点时，会触发【 】事件，当对象失 去焦点时将触发【 】事件。

细菌性肝脓肿的主要治疗是

A．抗生素治疗
B．穿刺抽脓，脓腔注入抗生素
C．切开引流
D．理疗
E．内引流术

购买儿童票的旅客可免费携带行包5千克。

中性粒细胞功能的检测选择（）

A.溶血空斑形成试验

B.硝酸四氮唑蓝还原试验

C.淋巴细胞转化试验

D.炭粒廓清试验

E.酶释放试验