----It's a long time ( ) I saw you last. ----Yes,and what a pity it is now that it will be a

Question

----It's a long time ( ) I saw you last. ----Yes,and what a pity it is now that it will be a long time ( ) we see each other again. A before since B since when C since before D when before Many people consider it ( ),from which a lot of children benefit. A a worth doing cause B a cause worth to do C a worthwhile cause D a worthless cause

Answer 1

这题选c吧！
since表示“自。。。之后”，动作发生在一件事情之后，如it's
a
long
time
since
i
saw
you
last.
自上次见到你之后有一段很长的时间。可以根据时态saw看出，事情发生在过去。
before表示“在。。。之前”，动作发生在一件事之前，如it
will
be
a
long
time
before
we
see
each
other
again在我下次再见到你会有一段很长的时间，从时态will可以看出，事情发生在将来。
when表示“当。。。。”，动作与事件是同时发生的！