A boy lost his arms in an accident and his father lost his life. Since then, he had to 31_ the arms of his younger brother. Except for writing with his toes(脚趾头), he could hardly do
I、卤素化学丰富多彩，能形成卤化物、卤素互化物、多卤化物等多种类型的化合物． （1）①HClO4、②HIO4、③H5IO6 的酸性由强到弱的顺序为 （填序号
On snowy days, you have to drive very ____ to avoid traffic accidents. A．cautiously B．neatly C．smoothly D．properly
古希腊城邦政治的核心力量是 A.执政官 B.贵族 C.公民 D.首席将军
2009年9月18日，中共十七届四中全会通过《中共中央关于加强和改进新形势下党的建设若干重大问题的决定》，强调指出要加强建设 A．学习型社会
Round eyes, round head, round ears, round body! What is this lovely little animal? He looks like a bear． But he is not a bear．He’s a KOALA． People in Australia love koala and tak
如图表示苍鹰捕鸽时，鸽群大小与攻击成功率（图中的矩形）及鸽群对鹰的反应距离图中的折线）之间的关系图．据图判断错误的是（ ）
Radium salts, which have been found to _____ in bones, give rise to cancers of the bone. A. pile up B. build up C. keep up D. pull up
(2) 
，(2) 原方程无解解析:
得
