Not matched records in sql using joins

Question

Hi all ,

Below i have two tables , 1st table contain 12 records and second one contain 8 records. now i need to  get remain 4 records only not with 8 records using joins in sql. i have tried below query  but still am not getting .please help on this

 

Select DISTINCT it.ShapeName,it.Intervalyear,it.IntervalMonth from @yearTable yt

left JOIN @IntervalTable it on yt.NumDays=it.IntervalNumDays

where  it.Intervalyear is null and it.IntervalNumDays='2018'