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]
到底
dào dǐㄉㄠˋ ㄉㄧˇ
finally; in the end; when all is said and done[cedict]
发生
fā shēngㄈㄚ ㄕㄥ
to happen; to occur; to take place; to break out[cedict]