【C6】A．surveyingB．surveyedC．to surveyD．having surveyed

【C6】A．asB．withC．thanD．to

【C6】A．inB．ofC．atD．to

【C6】A．having carriedB．to carryC．carryingD．carried

【C6】A．reachB．reachingC．to reachD．to reaching

【C6】A．readingB．to readC．readD．doing

【C6】A．assistant"sB．professor"sC．student"sD．librarian"s