“张口惊视的”可以翻译为 “with one's mouth agape in astonishment” 或者更简洁地表达为 “staring open-mouthed in shock/amazement” 。
“with one's mouth agape in astonishment” 强调了因惊讶而张大嘴巴的状态，“agape” 表示“张着口的”；“staring open-mouthed in shock/amazement” 则更侧重于描述人因震惊或惊奇而目瞪口呆、张着嘴看的神情。具体使用哪个表达可以根据语境和想要强调的侧重点来选择。