It is so heavy a rain that .对吗?应不应该有a

It is so heavy a rain that .对吗?应不应该有a there is a rain,it rains___.(heavy) I wonder why it is so dark.There _____be a heavy rain coming It is reported that there will be a heavy rain ___ the hike It seems that there______a heavy rain this afternoon.A.will It's raining very( )What a ( )rain it is(heavy) The　rain　is　so　heavy　that　it　is　just　 like＿＿（pour）　water　dow (How\What\What a)heavy rain it is! It is a heavy rain.(改为同义句) what a heavy rain it is 可以,那么 what a fine weather it is toda It’s really a pity that the heavy rain ______ to go for a pi _ rain it is!A.How a heavy B.What a heavy C.How thick D.What