This is the first time I ask a question here and I hope someone can help me out. My question about English language is related to music, thus, although I can be wrong, I think it would be good to write about some musical concepts to help you to help me. The conception of time in music is related to the way we feel the rhythm. We usually write music according to stressed and unstressed pulses, which causes a song to be divided in smaller parts called measures. Within the measures we have the strong and weak beats. Along with the rhythm, there are chords that are changed according to way the song was composed. Sometimes a chord can last for a whole measure, other times there are two or more chords that last small portions of the rhythm inside the measure. Suppose there are 2 chords within a measure of 4 beats. The first chord sounds from the first beat of the measure until the middle (or first half part) of the second beat. Then other chord starts to be used from the middle of the second beat until the end of the measure as shown in the figure below:
My question is: Is it wrong to say that the first chord lasts from the beginning of the measure until the middle of the second beat or would it be better to say that the first chord is used from the beginning of the measure until the middle of the second beat when the other chord will start to be used? I'm very confused about this. I'm not sure if I can say that the chord lasts, remains, is used for a part of the measure, or even sounds from the beginning until a given part of the measure. Could you help me please?
This is the real musical example:
Best regards, Renato.