A person shouldn't buy insurance protection that really isn't necessary.

一个人不应该买不必要的保险。

youdao

youdao

It may be necessary to buy a new one.

也许有必要买个新的了。

《牛津词典》

A young man who had the money to buy the supplies and the necessary tickets to travel to Alaska usually landed at the little port of Skagway.

VOA: special.2009.02.04

By selling on strength you have the cash necessary to buy on weakness.

FORBES: Overvalued Fundamentals And Overbought Technicals Means It's Time To Look To Reduce Market Exposures

We can't buy necessary medication because prices go up by 70% a day.

BBC: Iran police clash with protesters over currency crisis

Also, online competitors who are currently shipping these lower dollar purchases for free are subsidizing the freight and this is not a sustainable practice, so it is only necessary for Best Buy to weather the storm until online retailers discontinue this practice.

FORBES: Move up http://i.forbesimg.com t Move down