我 经常听到孩子们在公园里面玩的声音.
hear sb do sth 听到某人做某事
英语里没有find sb do sth 这个搭配.另外,find sb doing sth意思是发现某人正在做某事.
find只接 doing eg .i found him running just now.
find 还有种用法：find it +adj.+to do
eg.i find it useful to learn english well.