には
文法の解説は英語です。
用法
には indicates purpose in general statements (often stating the speaker's judgement about an action in terms of its effectiveness, convenience, necessity, etc.). には can also mean "when". Verbs or noun precede には. Note that when ために is used, the predicate in the main clause describe an action. "To; In order to; for; the purpose of; when"
例文
漢字を覚えるには、フラッシュカードを作るのが一番です
In order to remember Kanji, making Flashcards is the best way.
東京から京都に行くには、新幹線が速くて便利ですよ
To travel from Tokyo to Kyoto, the Shinkansen is fast and convenient.