It's more useful to remember sentences than individual words.
こんにちは! ご質問ありがとうございます。
ご質問について、いくつか言い方が考えられますが、例えば、 It's more useful to remember sentences than individual words. 『単語よりも文章を覚える方が役に立つ』
また少し変えて Learning sentences helps you improve your English more effectively than just learning words. や Understanding sentences is more beneficial than memorizing single words. というようにも表現できます。