The day that is directly before June 1 is May 31; however if you are referring to the day of week as of this year's upcoming May 31, then the day is Thursday.
The last day of June is June 30th. It marks the end of the month before July begins.
June 1, 1975 was a Sunday
June 1 1990 was a Friday.
1 June 1991 was a Saturday.
June 1 1987 was a Monday.
1 June 1796 was a Wednesday.
Fathers' Day is the third Sunday of June, which makes it the Sunday that falls after June 14 and before June 22.
June 1 1973 was on a Friday.
1 June 1951 was a Friday.
June 1 1975 was on a Sunday.
June 1, 1945 was on a Friday.
June 1 2005 was a Wednesday.