His parents don't allow him ________ computer games. They think they are bad for his studies.
A:play
B:played
C:to play
D:playing
血小板会释放出一种物质,使血液
小新和同学一起用硬纸板搭建了图示的轨道,测量小球运动的平均速度.
请补写出下列名句名篇中的空缺部分。
①顺风而呼,____,而闻者彰。(荀子《劝学》)
②____,以手抚膺坐长叹。(李白《蜀道难》)
③大弦嘈嘈如急雨,____。(白居易《琵琶行》)
④____,春与秋其代序。(屈原《离骚》)
⑤纵一苇之所如,____。(苏轼《赤壁赋》)
⑥____,用之如泥沙?(杜牧《阿房宫赋》)
⑦文章,经国之大业,____。(曹丕《典论》)
⑧操千曲而后晓声,____。(刘勰《文心雕龙》)