(i) In the zoo, the tiger paces restlessly in a small cage; in its natural habitat, it would be freely lurking in shadows and sliding through long grass near a watering hole.
(ii) The speaker insinuates that the tiger is a powerful predator by nature, whose habitat is the jungle's edge. Terrorising villages is its natural, instinctive behaviour — not a sign of cruelty, but of its wild, free existence.
(iii) The poet uses vivid imagery to highlight the tiger's confinement and suppressed anger. "Few steps of his cage" shows its cramped space. "Pads of velvet quiet" and "quiet rage" suggest silent, bottled-up fury. Contrasting images — lurking in grass, baring fangs — show what freedom looks like, making the captivity more painful.
(iv) "Suppressed anger" (or "silent fury") would correctly substitute 'quiet rage', as the tiger is inwardly furious but outwardly calm, unable to express its anger freely within the cage.
Source: "A Tiger in the Zoo" by Leslie Norris, First Flight, Chapter 1 (Poem)
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