摘要： While flying, a bat makes a sound which hits things and comes back to its ears. In this way it’s able to know the things are and avoid bumping into them. A. how B. where C. what D. which
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While flying, a bat(蝙蝠)makes a sound which hits things and comes back to its ears．In this way it’s able to know ________ the things are and avoid bumping into them．
- A.how
- B.where
- C.what
- D.which