one; 1; single; a (article); as soon as; entire; whole; all; throughout[cedict]
上
shàngㄕㄤˋ
on; on top; upon; first (of two parts); previous or last (week etc); upper; higher; above; previous; to climb; to go into; above; to go up; to attend (class or university); third tone of putonghua[cedict]
一下
yī xiàㄧ ㄒㄧㄚˋ
(used after a verb) give it a go; to do (sth for a bit to give it a try); one time; once; in a while; all of a sudden; all at once[cedict]