题目

Thursday is ________ Wednesday and Friday. 答案：【答案】between【解析】句意：星期四在星期三和星期五之间。根据“Thursday is…Wednesday and Friday”及常识，可知，此处用between…and表示“在……之间”，故填between。如图，△ABC中，AD为中线，DE⊥AB于E，DF⊥AC于F，AB=3，AC=4，DF=1.5，则DE= ．