He_____ to bed until eleven last nightA. went B. not go C. didn't go D. goes 答案:【答案】C【解析】考查时态。句意:昨天晚上直到11点他才去睡觉。昨天晚上应用过去时态,not...until...直到.......才。故选C如图, 是的角平分线, ,垂足为, , 和的面积分别为和,则的面积为( ).A. B. C. D.
C
【解析】过点D作DH⊥AC于点H,
由AD是△ABC的角平分线,且DF⊥AB,DH⊥AC,
则DF=DH,
在Rt△DEF与Rt△DGH中,DE=DG,DF=DH,
∴△DEF≌△DGH,
∴S△DEF=S△DGH,
∵S△ADF=20,S△ADE=18,
∴S△DEF=20-18=2=S△DGH,
∵AD=AD,DF=DH,根据勾股定理得...