读句画图:如图,直线CD与直线AB相交于C,根据下列语句画图:
(1)过点P作PQ∥CD,交AB于点Q;
(2)过点P作PR⊥CD,垂足为R.
人体最大的消化腺和最大的内分泌腺是( )
—That's great. But I don't know___________ it.