preventative maintenance是什么意思

preventative maintenance是什么意思 翻译（学术论文）Few independent people will have the background able to analyze whathappened let alone provide a preventative solution. Need to track down time on the machines for a better Total Preventative Maintenance (TPM) system.哪位帮我分析下句子结构,意思我懂,结构不懂. it has proved or it has been provedWhich one is correct?(1) or (2)1)Preventative medicine has proved to be the most effective way of reducing the incidence of fatal childhood diseases.2)Preventative medicine has been proved to be the most effective w 英文句子语法if preventative action is going to work ,you really do have to have everyone on board .怎样理解 do have to have everyone on board 这一句? 英语翻译not until beginning of the twentieth century was it recognized that certain substances were essential in the diet to prevent or cure come disease.these substances are now known as vitamins.they are vital for growth,good health,and mainten