首字母填空bats are the only fiying "animals " .it is known to all

首字母填空
bats are the only fiying "animals " .it is known to all that they can not see very well."as b____as a bat" is often heard.yet,they have no trouble flying on the darkest nights and f_____ their way round very well.why can bats fiy and see at night?they fly by "radar".the bat's radar works the same way a_____ the radar on ships and planes.as a bat flies through the air,it makes a sound.i_____ the sounds hit things,they will come back and the bat's ears will receive the message.in this way,the bat can know where the things are.bats go ou for f______ at night.in the daytime,they hang in some dark places.