One of
the Mamas and the Papas' most recognizable hits (in June,
1966),
I saw her again carries all their trademarks:
There can be no doubt that Phillips/Doherty and Lennon/McCartney admired and inspired each other's work.
A good illustration is Paperback writer / Rain, the Beatles single released in the same month of June, 1966: with all the differences in finishing listed above, the harmonic basis, especially in Rain, is the same.
However, I saw her again has a bridge thrown in with a non-obvious key change.
(Lyrics by John Phillips and Dennis Doherty:)
I saw her again last night
and you know that I shouldn't
To string her along's just not right
If I couldn't I wouldn't
But what can I do, I'm lonely too
and it makes me feel so good to know
you'll never leave me
I'm in way over my head
Now she thinks that I love her
Because that's what I said
though I never think of her
But what can I do, I'm lonely too
and it makes me feel so good to know
you'll never leave me
Every time I see that girl
you know I wanna lay down and die
But I really need that girl
Don't know why I'm livin' a lie
It makes me wanna cry
(lyrics taken from Markus Klenk's site)