【C6】A．inB．ofC．atD．to

A．onB．ofC．atD．by

A．inB．onC．atD．to

A．inB．byC．atD．on

【C17】A．onB．ofC．atD．in

【C2】A．inB．ofC．upD．to

There are trees ____ all shapes on the hill.A: inB: ofC: atD: by