Tom took a taxi to the airport, only _____ his plane high up in the sky.

A．finding

B．to find

C．being found

D．to have found

DF4D型机车试运中冷却水系统管路检查项目包括（）

A.各管路接头和各种截止阀有无泄漏

B.热风机管路系统各处有无泄漏

C.各放气阀和放水阀作用是否良好

D.膨胀水箱即补水管等各处有无泄漏