both之用法-十分

Both可用作限定詞(determiner)，解兩個、兩個都，如：
Both (the) women were French.（兩名婦女都是法國人）。
除了用作 限定詞外，它還可用作不定代名詞(indefinite pronoun)，如：
She has written two novels, both of which have been made into television series
both其實也可用做副詞（在此不談）
但不論用做限定詞，或不定代名詞，both之後的名詞都要跟眾數形。
所以
Both (the) volumes remain constant.(the可有可無）
或
Both of the volumes remain constant都正確（留意要有the）
希望幫到你！

Both volumes remain constant
(Both 之後不用加 preposition "of" , volumes 眾數的 present tense 係 remain)