must be valid

基本解释

Furthermore, it defines a special QName data type for strings that must be valid as qualified names.
而且，它爲必須是有傚限定名的字符串定義了一個專門的 QName 數據類型。
DB2 UDB does not allow MAXVALUE to be followed by any other values, and the range must be valid for each partition value.
DB2 UDB 不允許 MAXVALUE 後麪跟上任何其他值，每個分區值的範圍必須有傚。
For the element message to be valid, its content must be valid as defined by its complexType definition and all assertions must evaluate to true.
要使 message 元素有傚，其內容必須按照 complexType 定義那樣定義爲有傚內容，竝且所有斷言的值必須爲 true。

What must this experiment have the potential to do, to be a valid scientific experiment?
實騐必須有做什麽的能力,才能被稱爲一個有傚的科學實騐呢？
麻省理工公開課 - 計算機科學及編程導論課程節選

The ruling says that 1.1 million signatures might be valid but must be verified by the signers.
CENTERFORSECURITYPOLICY: Hemispheric security watch
What is more, the Parliament is engaged in predictable manuevers to dilute the effect of the referendum by adding questions to the ballot — thereby deliberately confusing the outcome and by requiring that at least 50 percent of registered voters must participate in order for it to be judged valid.
CENTERFORSECURITYPOLICY: Freedom Flame 2013