The phrase "were startled" refers to the sudden shock or surprise a person experiences when confronted with something unexpected or frightening. Some alternatives to this phrase include "were taken aback," "were surprised," "were startled," "were frightened," and "were shocked." Each of these synonyms conveys a unique sense of alarm or surprise, with "taken aback" suggesting a temporary mental confusion, "surprised" indicating a more moderate reaction, and "startled," "frightened," and "shocked" referring to more intense responses. Whether describing a character's reactions in a novel or recounting a personal experience, using synonyms for "were startled" can add variety and depth to your writing.