have a look 、look at 、take a look 、take a look at 有什么区别?貌似有几

have a look是“看一看”的意思 短语：have a look at sth.
look at是“看着……”的意思,后接代词宾格或名词
take a look是“注视”的意思 短语：take a look at sth.