文法・語法チェック---4

動名詞の使い方（on ...ing, without ...ingは必須）、知覚動詞+目的語＋...ing（原形不定詞だけでなく、現在分詞、過去分詞もくる）、関係代名詞目的格の省略

on ...ing, see + O + ...ing
On approaching the mouth of the alleyway I saw Dementors running -'(Phoenix)

rarely, see + O + ...ing
He had rarely seen Mr. or Mrs. Weasley wearing anything that the Dursleys would call "normal." (the fire of the goblet)

as though以下の構造が見えますか？
Her arms were folded, her lips were pursed, and she seemed to be chewing her tongue, as though biting back the furious diatribe she longed to throw at Harry.
(the fire of the goblet)