preg_match_all提取信息

Question

<p class=MsoNormal style='mso-layout-grid-align:none;text-autospace:none'><span
lang=EN-US style='font-size:12.0pt;mso-bidi-font-size:18.0pt'>2</span><span
style='font-size:12.0pt;mso-bidi-font-size:18.0pt;font-family:宋体;mso-ascii-font-family:
"Times New Roman";mso-hansi-font-family:"Times New Roman"'>：</span><span
style='font-size:12.0pt;font-family:宋体;mso-hansi-font-family:"Times New Roman";
mso-bidi-font-family:宋体;color:black;mso-ansi-language:ZH-CN'>晚上12时我在(<span
style='mso-spacerun:yes'>&nbsp;&nbsp;&nbsp;&nbsp; </span>)。<o:p></o:p></span></p><p class=MsoNormal style='mso-layout-grid-align:none;text-autospace:none'><span
lang=EN-US style='font-size:12.0pt;mso-bidi-font-size:18.0pt'>3</span><span
style='font-size:12.0pt;mso-bidi-font-size:18.0pt;font-family:宋体;mso-ascii-font-family:
"Times New Roman";mso-hansi-font-family:"Times New Roman"'>：</span><span
style='font-size:12.0pt;font-family:宋体;mso-hansi-font-family:"Times New Roman";
mso-bidi-font-family:宋体;color:black;mso-ansi-language:ZH-CN'>中午，我们学校(<span
style='mso-spacerun:yes'>&nbsp;&nbsp;&nbsp;&nbsp; </span>)时上课。<o:p></o:p></span></p><?
preg_match("/<p[^>]*>(.*?)<\/p>/",$str,$all);
?>如何提取里面的中文啊,这样好象不行啊。
提出的格式为
1:晚上12时我在2:中午，我们学校（）时上课把他们放入数组
array('晚上12时我在','中午，我们学校（）时上课');