I _ carefully ,but _nothing.大概意思是什么

I _ carefully ,but _nothing.大概意思是什么 I always______the teacher carefully,but I 39.I listened carefully,but I heard . I listened carefully but I heard 改错I listened carefully,but nothing heard. I __ very carefully,but I can ____ nothing. I listened carefully but I heard anything.（改错） I listen to others carefully什么意思 I____my teacher carefully,but I can't _____her. 选 择 ------ her carefully ,but I --- --nothing .见下面补充 but I n____ to listen very carefully to understand it Some animals are dangerous,but some are_ _ i _ _ _ _ _