中 => While (Lasting) N3
Continuous
途中で/途中に => on the way; in the middle of ~ N4
中 => During the period (Term) N3
Time
[中心「ちゅうしん」]に => With A as the center N2
Miscellaneous
を中心に => focused on; centered on~ N2
最中に => while; during; in the middle of ~ N3
や => ... or... N5
Line up, list
や否や => as soon as; the moment ~ N1
途中 (は) => on the way; in the middle of ~ N3
Halfway
や、やいなや => As soon as A, B N1
Time, Situation
中 => Throughout, all over, during the course of N5
Time
や => and; or N5