The Foreign Minister's press conference was a clear effort to preempt a damaging disclosure.外交部长举行的记者招待会显然旨在先发制人，以防止危害极大的泄密。Smoking is ruinous to your health.吸烟对健康的危害极大。The heavy frost in late spring was ruinous to the crops.暮春的浓霜对庄稼危害极大。Frost and wet are the lethal combination for plants.霜雨天气对植物危害极大。