In extreme weather a worn tyre can break easily it’s mended as is often the case.A. whe

问题补充：

In extreme weather, a worn tyre can break easily it’s mended, as is often the case.

A. when

B. where

C. which

D. that

答案：

A. when

(答案→)B. where

C. which

D. that

解析：考查地点状语：where引导地点状语=at the place where，在…地方，句意：在极端天气，旧轮胎在修补的地方很容易坏，情况经常是这样的。