What are the different types of major scale 7th chords and how are they constructed?

The different types of major scale 7th chords are major 7th, dominant 7th, and minor 7th. They are constructed by taking the 1st, 3rd, 5th, and 7th notes of the major scale. The major 7th chord has a major 3rd and a major 7th, the dominant 7th chord has a major 3rd and a minor 7th, and the minor 7th chord has a minor 3rd and a minor 7th.