题目

109. ---What was the food like?     ---___________________.  A.Nothing special                         B. Special nothing      C. Nothing specially                        D. Specially nothing 答案：A如图，长方形ABCD中AD∥BC，边AB=4，BC=8．将此长方形沿EF折叠，使点D与点B重合，点C落在点G处．（1）试判断△BEF的形状，并说明理由；（2）求BF的长．