Hello could you please give me a key question and an outline on this passage please?
(the turn of the screw)
I scarce know how to put my story into words that shall be a credible picture of my state of mind; but I was in these days literally able to find a joy in the extraordinary flight of heroism the occasion demanded of me. I now saw that I had been asked for a service admirable and difficult; and there would be a greatness in letting it be seen—oh, in the right quarter!—that I could succeed where many another girl might have failed. It was an immense help to me—I confess I rather applaud myself as I look back!—that I saw my service so strongly and so simply. I was there to protect and defend the little creatures in the world the most bereaved and the most lovable, the appeal of whose helplessness had suddenly become only too explicit, a deep, constant ache of one’s own committed heart. We were cut off, really, together; we were united in our danger. They had nothing but me, and I—well, I had them. It was in short a magnificent chance. This chance presented itself to me in an image richly material. I was a screen—I was to stand before them. The more I saw, the less they would. I began to watch them in a stifled suspense, a disguised excitement that might well, had it continued too long, have turned to something like madness. What saved me, as I now see, was that it turned to something else altogether. It didn’t last as suspense—it was superseded by horrible proofs. Proofs, I say, yes—from the moment I really took hold.
This moment dated from an afternoon hour that I happened to spend in the grounds with the younger of my pupils alone. We had left Miles indoors, on the red cushion of a deep window seat; he had wished to finish a book, and I had been glad to encourage a purpose so laudable in a young man whose only defect was an occasional excess of the restless. His sister, on the contrary, had been alert to come out, and I strolled with her half an hour, seeking the shade, for the sun was still high and the day exceptionally warm. I was aware afresh, with her, as we went, of how, like her brother, she contrived—it was the charming thing in both children—to let me alone without appearing to drop me and to accompany me without appearing to surround. They were never importunate and yet never listless. My attention to them all really went to seeing them amuse themselves immensely without me: this was a spectacle they seemed actively to prepare and that engaged me as an active admirer.
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