—Have you heard that George quit his job?
—Yeah, but I can't________why he did so.
A．put out B．figure out
C．carry out D．send out
—Tony, you must have noticed the student who broke the glass.
—I'm sorry.I________attentively.
A．studied B．was studying
C．am studying D．would study
—Sorry for the delay.I got lost in the mountain.
—That's OK.You're safe and that's what________.
A．does B．works
C．stays D．counts
—Tom has been fired by his boss.
—________？As far as I know，he is a hardworking and considerate fellow.
A．Why not B．How come
C．What then D．So what
Annoyed by the salesman's bad manner，John chose ________of the two computers on sale and left.
A．all B．either
C．neither D．none
Time is of no importance to great thoughts，________ are as fresh today as when they first passed through thinkers' minds ages ago.
A．what B．that C．which D．where
