陕西省定边县第四中学高中英语选修九《Unit 2 Sailing the oceans Language Points》课件（人教版）.ppt

e.g. The minimum requirements for the job are a degree and two years’ experience. 该工作的最低要求是要有学位和两年 的工作经验。 You must get a minimum of 40 questions right to pass the examination. 你最少必须答对40道题才能通过考试。 There was no secure method of measuring longitude until the 17th century when the British solved this theoretical problem. secure adj. 安全的, 可靠的, 放心的, 无虑的 v. 保护, 使安全 e.g. Our house is secure from flood. 我们的房子没有被淹的危险。 Page 13 security n.安全，保安，保护 e.g. Security was tight during the President’s visit. 总统来访期间，保安工作十分严 密。 For security reasons the visitors were searched. 为了安全起见，来宾受到了检查。 Some measures are needed to secure the bank from a flood. 这道堤防需要采取一些措施, 免得被洪水冲坏。 2. The compass has a special magnetic pointer which always indicates the North Pole. magnetic adj. 磁的, 有磁性的, 有吸引 力的 magnet n. 磁体, 磁铁 a magnetic recorder 磁录音机 e.g. a magnetic compass bearing 可分辨磁极方向的罗盘 a magnetic person 有魅力的人 The iron has lost its magnetic force. 这铁已失去磁力。 3. Then he could tell if he was sailing on his correct rather than a random course. random n. 随意, 任意 adj. 任意的, 随便的, 胡乱的 make a random choice 任意选择 at random = aimlessly; without any plan 随机，随便 e.g. The travelers at the airport were searched at random. （搜查人员对）机场上的旅客随便选 几个人加以搜查。 Soiled dishes were piled at random. 脏碟子乱七八糟地堆着。 4. It was awkward to use as one of the points of reference was the moving ship itself. awkward adj. 难使用的, 笨拙的, 尴尬的; 棘手的, 难处理的 An awkward situation arose during the peace talks. 在和平谈判中出现了棘手的情况。 e.g. There was an awkward silence, when no one knew what to say. 当谁都不知道说什么时，出现了令人尴 尬的沉默。 5. This was a more precise and simplified version of the astrolabe. precise adj. 精确的, 准确的 precision n. 精