有必要

• It will be useful to summarize the relevant gaussian formulae .
  有必要概括地讲一下有关的高斯公式。
• It becomes necessary to visually classify a large number of samples .
  有必要对大量样品进行目测分类。
• I have been unable to resist the temptation to include a final chapter .
  我觉得很有必要增加最后一章。
• It bears study .
  有必要进行研究。
• Let us risk seeming repetitious explanation, in order to drive it home .
  为了便于理解，有必要作进一步说明。
• It is necessary for men to enter into a compact mutually among themselves .
  人们之间有必要共同缔结一种契约。
• It would be beneficial to review the fundamental theory of electrostatics .
  因此有必要对静电的基本理论作一简介。
• Reforming consumer subsidy programs, though desirable, is not easy .
  改革消费补贴方案虽然有必要，但实行起来并非易事。
• Twenty divisions of troops were to be brought into the north-west if necessary .
  如有必要，要向西北派二十个师的兵力。
• Nevertheless, i feel i ought to tell you that it is the cop that counts .
  尽管如此，我仍感到有必要告诉你，关键在于警察。