---Hi, Tracy, you looked tired.

---I am tired. I______the living room all day.

A．painted

B．had painted

C．having been painting

D．have painted

建筑接近限界指在铁路线上，为确保行车安全，靠近轨道的（）及设备，不得侵入一条固定的轮廓线。

A、站台

B、建筑物

C、隧道边墙

D、信号机