opinion、view、sentiment与idea这些名词均含“意见，看法，见解”之意。

opinion : 普通用词，使用广泛。多指初步的或缺证据支持因而不十分肯定的意见或看法。

• We were invited to give our opinions about how the work should be done.
  我们应邀就如何开展工作提出意见。
• I've recently changed my opinion of her.
  我最近改变了对她的看法。
• Everyone had an opinion on the subject.
  大家对这个问题都有自己的看法。

view : 侧重指个人对较广泛或重大问题所持的看法，常用复数形式。

• to have different/conflicting/opposing views
  有不同的 / 矛盾的 / 相反的观点
• to have strong political views
  持强硬的政治观点
• His views on the subject were well known.
  他对这个问题的看法众所周知。

sentiment : 着重指基于情感而非推理所得出的，已经固定了的看法，常用复数形式。

• the spread of nationalist sentiments
  民族主义情绪的传播
• This is a sentiment I wholeheartedly agree with.
  这种态度我完全赞同。
• Public sentiment is against any change to the law.
  公众的意见是反对对该法律作任何修改。

idea : 普通用词，通常指凭感觉和想象所形成的看法或意见。

• He has some very strange ideas about education.
  他对教育有些非常奇怪的看法。
• Some of his ideas about democracy are entirely his own.
  他关于民主的一些观点完全是他自己的创见。