王爷爷家有一块长方形菜地的长是8米,宽是4米,在这块菜地的三边围上篱笆,至少需要多长的篱笆?
11月23日,我国宣布:划设 防空识别区。防空识别区是基于国防需要划设的预警区域。( )
His wife, to whom he _____ for 20 years, died of cancer last Thursday. ( )
结合课文《热爱生命》内容理解下列句子,回答问题。