I think this is a good idea.(改为否定句) I _ _ this _ a good idea

Having a bake sale is a good idea 改为同义句 ___a good idea____ _ this is a good idea 改为同义句this is ＿I＿ I think it is a good idea.（改为否定句）…… I have a good idea .(改为否定句） I have a good idea.(否定句) I think he has a good idea.改为否定句,has要不要变回have? i think it was a good idea to watch tv 改为否定句 i think this is a good idea.(改为宾语从句) please teii me——,——,——. I don't think this is a good idea,____ _____.(完成反意疑问句） This is a Japanese car.(改为否定句) This _ _ a Japanese car. i think this is a good way of improving your english.改为否定句 I think this is a good way to keep healthy.(改为否定句)