问题
单项选择题
| The safety of ships at sea does not depend only on the arrangements made in the ships themselves. Dangerous coasts and rocks may be seen in the daytime, (51) they are a threat to safe navigation at night. Lighthouses are therefore erected at such places to (52) sailors of the danger. Modern lighthouses are put up at all dangerous places near the courses (53) by ships. On some rocky coasts several lighthouses may be built not far from each other, and (54) the sailors on a ship may know which is which, they have (55) arrangements of lights. One lighthouse will give a single flash at regular (56) , another may give two flashes; a third may give two followed by one; and so on. (57) watching the lights the navigator is able to decide exactly where he is, and he can set his (58) with confidence. In the approaches to some ports two continuous lights are set up, one above (59) but some distance behind; when they appear from the sea one above the other, the ship is on the right course; but if they do not, the captain knows that he is (60) his course and likely to strike a rock or the bottom of the sea. |
A．so that
B．in order that
C．even though
D．now that
答案
参考答案：B
解析：从上下文看，本句相对于下句应该是表示目的，句子的意思是说，“为了让船上的水手知道哪座是哪座，灯塔的灯有不同的安排。”A项so that和B项in order that均可表示目的，但so that引导目的状语从句时必须放在主句之后，故用在这里不合适，正确答案应选B。C项even though“尽管”表示让步关系，D项now that“因为，既然”表示原因，它们用在这里均与上下文的意思不符。