need·ful /ˈniːdfəl/ adjectiveadj old use MUSTnecessary 必要的,需要的 needful expenditure 必要的开支
needful• It was not spoken of but drawn upon when it was needful.• The proposed discount will go only a certain way towards doing what is needful.• He might be seen returning, and it was needful he should come by the way he would have taken to Longner.• To effect the separation it was needful that the particle size was more or less the same.• It will be needful to find them, Master Hussey.