英语时态里面为什么有时加has有时不加呢

你问的是现在完成时吧。。。

1.宾语从句的主语：一随主，二随宾，三不变。e.g.(1)ShesaidIwillgohome.改：Shesaidthatshewouldgohome.（一随主）(2)ShesaidtomeYoucangowithme..改ShesaidtomethatIcouldgowithher.(二不变)(3)ShesaidtomeHewillgohome.改Shesaidtomethathewouldgohome.(三不变)2.宾语从句中注意时态1.若主语为一般过去时，则宾语从句的时态要变为过去的某一时态。e.g.(1)HesaidIwilgohome.“改Hesaidthathewouldgohome.(一般将来时改为过去将来时)（2）HesaidIhavehadlunch.改Hesaidthathehadhadlunch.(现在完成时改为过去完成时)(3)HesaidIknowalotabouttheteacher.改Hesaidthatheknewalotabouttheteacher.(一般现在时改为一般过去时)（4）HesaidIhadlunch.Hesaidthathehadhadlunch.(一般过去时改为过去完成时）(5)HesaidIamplayinggames改Hesaidthathewasplayinggames.(现在进行时改为过去进行时）特殊HesaidTheearthgoesaroundthesun.改Hesaidthattheearthgoesaroungthesun.(当直接引语中表示客观事实时，时态不受主句影响）3.直接引语变间接引语时，要注意时间状语的改变。e.g.Hesaid‘Iamlisteningtomusicnow.改Hesaidthathewaslisteningtomusicthen.(此句中now改为then)后面不举例了，时间状语按下面改就对了now=thentoday=thatdaytonight=thatnightthismorning\week=thatmorning\weektomorrow=thefollowing\nextdayyesterday=thedaybeforelastmouth=themonthbeforeago=beforehere=there（上面左为直接引语中的时间状语，右为间接引语的时间状语）4.最后是指示代词要变this改为thatthese改为those

这是我总结的，希望对你有用