A、 Disconnect the connection. This connection is downstream of the valve.
B、 Disconnect the connection. The valve is downstream of the connection.
C、 Disconnect the valve. The valve is downstream of the connection.
答案：A
A、 Disconnect the connection. This connection is downstream of the valve.
B、 Disconnect the connection. The valve is downstream of the connection.
C、 Disconnect the valve. The valve is downstream of the connection.
答案：A
A. Use the specified one if the equivalent material is not available.
B. Use the available equivalent one if no material is specified.
C. If you can not get the specified material, use an equivalent.
A. These tests shall be independent.
B. These tests shall be self-locking.
C. These tests shall be comprehensive.
解析：这道题考察的是对英语词汇的理解能力。在题干中，我们需要理解"self-contained"这个词的含义。"Self-contained"意味着能够独立存在或运行，不需要依赖其他事物。因此，正确答案是A:These tests shall be independent。
举个生动有趣的例子来帮助理解，就好比一辆太空飞船必须是self-contained的，它需要携带足够的氧气、食物和水，不依赖外界资源。如果飞船不self-contained，就无法在太空中独立运行。所以，这道题的意思就是这些测试必须是独立的，不依赖其他因素。
A. Inspect the drain holes for obstruction.
B. Check for the drain holes for abrasion.
C. Check the drain holes for leakage.
A. Use white paper with good strength characteristics and enough weight and substance to eliminate excessive print leakage when printing on both sides.
B. Use good white paper with high strength quality and of adequate weight to delete excessive show-through when printed on both sides.
C. Use white paper with good strength and of sufficient weight and substance to prevent overmuch ink show-through the paper when printed on both sides.
A. When the light goes off, set the switch to NORMAL.
B. When the light is illuminated, move the switch to NORMAL.
C. When the light is extinguished, move the switch to NORMAL.
解析：这道题考察的是根据指示操作开关的能力。正确答案是B: 当灯亮起时，将开关设置为正常。这句话的意思是当灯被点亮时，你需要把开关设置为正常。选项A中的“goes off”表示灯熄灭，与题目中的“comes on”相反，所以不是正确答案。选项C中的“extinguished”也表示灯熄灭，与题目中的“illuminated”相反，所以也不是正确答案。
举个生动的例子来帮助理解：想象你在一个房间里，有一个开关控制着房间里的灯。当你看到灯亮起时，你需要把开关设置为NORMAL，这样灯就会保持亮着。所以正确答案是B。
A. If you drink contaminated water , illness must happen.
B. You may be in trouble, if you drink bacteria free water.
C. If you drink water that contains bacteria, you will get sick.
A. The compressing of the spring can cause the valve to open.
B. There is no change of the valve when the spring compresses.
C. After compressing of the spring, the valve goes to closed position.
A. When the cumulative revised pages (including back-up pages) exceeds 60% of the total pages of the manual, a reissue should be prepared.
B. If the updated pages, including back-up pages, were less than 60% of the total page of the manual, a new manual should be copied.
C. Up to 60% of total pages (including back-up pages) were accumulated by mistake, the manual should be rewritten.
A. This Section shall be clearly stated and cross-referenced to the proper paragraph in Section 2 of the Handbook which consists of limitations.
B. This Section contains limitations which shall be clearly stated and cross-referenced to the proper paragraph in Section 2 of the Handbook.
C. The proper paragraph in Section 2 of the Handbook shall describe and cross-reference this Section included in this limitations.
A. Vertical pages instead of horizontal are preferred for all types of publication.
B. Horizontal pages are more preferable for all types of publication than vertical ones.
C. Both vertical and horizontal pages are rather preferable for all types of publication.
