She has enough knowledge to work with.（最後の前置詞に注意）
不定詞の形容詞用法には４パターンある
① Phil has a lot of friends to support him.
② Phil has a large family to support.
③ Phil has a good income to support his family on.
④ Phil has no intention to support his family.
ごめんなさい、出典が不明です。