be necessary to造句

• These reference books are necessary to us .
  这些参考书是我们所必需的。
• Love is necessary to a successful union .
  美满的婚姻必定需要爱情。
• It is necessary to delimit the anomaly clearly .
  清楚地圈定异常是必要的。
• It is necessary to exterminate the post at the sawmill .
  必须端掉锯木厂边的哨所。
• Secondly it is necessary to define the applied load .
  其次，需要确定所作用的载荷。
• It is necessary to draw readers'attention to the catalogue .
  必须提醒读者去注意目录。
• It is necessary to have special detectors to pick it up .
  这需要用专门的探测器来测量。
• It is necessary to put up control experiments as far as possible .
  要尽可能进行对照实验。
• It is necessary to maintain surveillance on these meters .
  必须对这些仪表保持经常性的监测。
• It is necessary to know what the public perceives of banks .
  很有必要知道公众对银行的了解程度。
• It is necessary to move an appreciable mass of ink or lead .
  必须使一定数量的墨水或铅产生运动。
• In this situation it is necessary to rank the projects .
  在这种情况下，有必要对有关项目分等排列。
• As long as they lived, exertions would not be necessary to her .
  只要他们活着，是不需要她吃苦的。
• It is necessary to curtail or alter normally coexisting stimuli .
  必需消除或改变正常时并存的刺激。
• The result raises a hope that it is necessary to nip the bud .
  这个结果引起我们从根本上解决问题的希望。
• For proper combustion it is necessary to atomize the propellants .
  为了有效地进行燃烧，推进剂必须雾化。
• It is necessary to outline the promises upon which they should be based .
  必须明确这些项目基于什么前提。
• It is necessary to accept a substantial degree of state intervention .
  接受极大程度的国家干预是完全必要的。
• It would be necessary to connect a limiting resistor in series with the lamp .
  须用一个限流电阻同灯泡串联起来。
• An added voltage is necessary to overcome the barrier thus created .
  必须增加一个附加电压去克服这样引起的位垒。