hcard_guessgap_back">
	<div class="fcard_bg" src="pics/fcards0.png" sx=0 sy=0></div>
	<div class="fcard_center" style="height:2.5em">
	...用<i>递增</i> 间隔！
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</span>
<span id="flashcard_sci_a_front">
	<div id="fc_words" class="fcard_center" style="height:3.5em">
	记忆的实验科学的先驱者是...
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</span>
<span id="flashcard_sci_a_back">
	<div class="fcard_bg" src="pics/fcards0.png" sx=400 sy=0></div>
	<div id="fc_words" style="position: absolute; width: 250px; top: 60px; left:15