Good opportunities are rare and should be seized when they appear.
好机会很少出现，出现时应该把握。 (hao jihui hen shao chuxian, chuxian shi yinggai ba wo)
"Don't miss the chance, opportunity knocks but once."
"不要错过机会，机会只敲一次门。" (bu yao cuoguo jihui, jihui zhi qiao yi ci men)
an unusually large harvest
used to express how one understands or interprets something
the strength of a group depends on the weakest member
someone who is easy to understand or very honest
to add something extra, especially at the end
the last or most difficult challenge or area of exploration
