Thanks everybody for your opinion. Much appreciated!
So I boiled down the issue to:
1. The chord progression is very similar, but it is not a copyright-able feature.
2. The phrasing of the melody is almost exact.
My question is, although the issue is 'hard to win and not so copyright-able', do you guys agree with me that the above conclusion is just enough for somebody to brought up the case to the public to prove the morality of 'the composer'??
Another question is, my friend tell me that the theory behind those very similar chord is 'counterpoint', is it so?
What is the music theories that's going on to describe the similarity in those 'chords and phasing similarity'?
Thanks in advance.