Read it through once

PROSPERO. Soft, sir; one word more. [_Aside._] They are both in either’s powers. But this swift business I must uneasy make, lest too light winning Make the prize light. [_To Ferdinand._] One word more. I charge thee That thou attend me. Thou dost here usurp The name thou ow’st not; and hast put thyself Upon this island as a spy, to win it From me, the lord on ’t.