once harm____(do)to the environment,it takes years to have the system recovered.

once harm____(do)to the environment,it takes years to have the system recovered. Do you still remember you once said to me? i'm telling you once a___ not to do that ( )do you write to your parents?I write to them once a month根据回答提问 what are they going to do to him ...once and for all?'是啥意思? It's better to do the homework at once then to c()about it he was asked to do the experiment at once 怎么译 翻译:how often do you go to movies?和once a week. once he makes up his mind to do something,no one can hold him back she forget___(to do/doing)her homework and did it once again （ ）do you go to see your uncle?Once a month.括号里填什么 I said to him :Do it at once 转化成间接引语怎么写 ________(tell) once,he knew what to do.怎么填啊 如何翻译这句话：“You shouldn't try to do everything at once.” We do a big cleaning once a week to keep our classroom____.A.tidy B.clear it's best not to do it all at once.[[[[all? pls help to d/chk supplier do they hv available stock can del once order cfm Hard to recur once.