though warned of the danger,he still went skating on the thin ice.为什么warn不能用ing形式

Though he () of the danger,()the naughty boy didn't listen to meA was warned;yet Bwarned;/ Cwas warned;but Dis warning;/ Though __ of danger ,sightseers have been flocking to the site where Bin Laden lived.为什么填warned 而不是 being warned? though warned of the danger,he still went skating on the thin ice.为什么warn不能用ing形式 The public has been warned of the danger of pollution. The __( warn) warned us of the danger of fire we ( )to be careful of rats since the whole street was full of rubbishA.warned B.have warned C.have been warned D.were warning China warned of corruption 解释这句话The public has been warned of the danger of pollution. I warned him of the danger.这里为什么用of啊? the doctor warned the patient ____ smoking A of B against C at D for ______ many times,none of the boys dared swim in that river______ many times,none of the boys dared swim in that river.A.Having warned B.Been warned C.Having warning D.Having been warned He shou have been warned of the danger,so he was.为什么不是so he should? The weather station warned of severe snowfalls ahead.这里的ahead怎么翻译? ______ of danger in the street last night,she had to go home,with a friend following her.A.To be warned B.Warned C.Having warned D.Warning 翻译；he also warned the students not to drop out of school and follow the examples of himself The though of jumping out of the plane t____ her. Her most influential book ,Slient Spring,warned against the abuse of the power的出处,以及原文 英语翻译While admitting that this forecast was somewhat uncertain,the scientists warned against treating it as a cry of wolf.