one at a time

freely individually separately

severally

all by one's self apart autonomously by oneself exclusive of of one's own volition on one's own one by one singly solo unaided unrestrictedly unsupervised without regard to without support

together

dependently

alone independently personally

severally singly

apart by oneself distinctively exclusively one by one restrictedly without help

together

gradually in succession individually little by little separately singly step by step

independently personally solely

severally singly

apart clearly definitely disjointly distinctly one by one

together

separately severally

apart independently one by one particularly respectively

together