miàn / duì / tū / rú / qí / lái / de / wēi / xié / tā / yì / shí / dù / kǒu / guǒ / zú / bù / zhī / dào / gāi / rú / hé / yìng / duì

面对突如其来的威胁，他一时杜口裹足，不知道该如何应对。

Faced with the sudden threat, he was too frightened to speak or act and did not know how to respond.