function chgscr(num) {
	if(num==1){
	document.images.show0.src = "http://nihongopc.us/pcgif/pda22.jpg";
	}else if(num==2){
	document.images.show0.src = "http://nihongopc.us/pcgif/pda22.gif";
	}else if(num==3){
	document.images.show0.src = "http://nihongopc.us/pcgif/pda50.gif";
	}else if(num==9){
	document.images.show0.src = "http://nihongopc.us/pcgif/pda10.jpg";
	}

}