求翻译：完全依赖短期的通风处理。通风处理作为基本环保措施，对室内污染有改善作用，但因为多数有害物质会缓慢释放，长达3-15年，绝非几个月通风换气就能解决问题，在其密集散发期1-3年内，您要冒较大的致病、致癌风险;而且中国北方冬夏季需封闭门窗，况且多数居室、写字楼新风换气并不理想，通风作用会大大降低;另外以甲醛为例，它分游离、吸附、结合三种状态存在。只有游离状态的通风处理能消除，且须是正常风速的4倍以上。是什么意思？

Completely dependent on short-term ventilation. Ventilation processing as basic environmental measures, on indoor pollution has improve role, but because most harmful substances will slow release, up to 3-15 years, is not several months ventilation ventilation on can solution problem, in its intensive dissemination period 1-3 years within, you to risk larger of pathogenic, and carcinogenic risk; and China North winter summer required closed doors and Windows, besides most room, and Office fresh air ventilation does not ideal, ventilation role will greatly reduce; also to formaldehyde for cases, it min free, and adsorption, and combination three species state exists. Only the ventilation process can eliminate free State, and be more than 4 times the normal speed.