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]
那些
nà xiēㄋㄚˋ ㄒㄧㄝ
those[cedict]
梯级
tī jíㄊㄧ ㄐㄧˊ
stair; rung of a ladder[cedict]
去
qùㄑㄩˋ
to go; to leave; to remove; fourth tone of putonghua[cedict]