[单项选择]Essential safety ______ must be taken when attempting to patch up this electrical device.
A. measures
B. prerequisite
C. calculation
D. recommendation

[单项选择]The subject of safety must be placed at the top of the （）.
A. timetable
B. bulletin
C. routine
D. agenda

[单项选择]When were pulse rates taken


A. After every exercise period.
B. Every time the ratio of active riding was increased.
C. Every day.
D. After each step-test.

[单项选择]Automobiles must have certain safety devices such as seat belts and good brakes.（）
A. 汽车应有一定的安全性, 要有安全带和好的刹车。
B. 汽车有了安全带和好的刹车就是安全的。
C. 汽车应有安全装置, 比如安全带和好的刹车。
D. 汽车必须有安全带和好的刹车这两个安全装置。

[单项选择]__________ safety, you must keep all medicines away from children.


A. For the sake of
B. In the event of
C. On account of
D. With reference to

[单项选择]Steps must be taken to reduce administration costs.（）
A. government
B. management
C. organization
D. instruction

[单项选择]Effective measures must be taken to limit the number of tourists．
A. 对旅游者的数量必须采取有效的限制措施。
B. 应该采取有效的措施来约束大部分旅游者。
C. 我们必须采取有效的措施把大多数的旅游者限制起来。
D. 许多的旅游者因为我们有效的措施约束起来。

[单项选择]（）man must fear when traveling in space is radiation(辐射) from the sun.
A. Which
B. How
C. What
D. That

[单项选择]It must comply strictly in safety standards to be accepted by the public, and at the same time it must demonstrate that no health or environmental damage occurs.（　）
A. than
B. to
C. from
D. with

[单项选择]

Pressure Cooker (压力锅) Safety
When you are cooking with a pressure cooker, you should learn a few common sense (常识) rules:
1. Never leave the cooker unwatched when it is in use.
2. Add sufficient liquid but never past the recommended fill point. Overfilling the cooker may block the vent pipe (排气孔) and cause the cooker to explode.
3. Set the cooking time. Too much time may overcook the food or too much pressure may build up in the cooker. Too little time will lead to undercooked food.
4. If you are new to pressure cooking, follow the cooking instructions carefully. Heat and time can either result in a great meal or a ruined one.
5. Never try to force a pressure cooker cover open. Allow the cooker to cool or run it under cool water before trying to open the cover.
6. Clean the cooker thoroughly after each use. Mild detergent (洗涤剂) and hot water work the best. Do not use stove ash or sand for they may damage the cooker. The gask
A. keep the cooker under close watch
B. always keep the cooker half full
C. never leave the cooker empty
D. never turn off the stove

[单项选择]The best color pictures are taken when _________.


A. the sun is directly overhead
B. the range of highlights and shadows is large
C. the sun is lower in the sky
D. black and white film is used