if [sth] crops upexprexpression: Prepositional phrase, adverbial phrase, or other phrase or expression--for example, "behind the times," "on your own."
(should [sth] unexpected arise)
如果突然发生某事 rú guǒ tū rán fā shēng mǒu shì
I plan to come to the party, but will let you know if something crops up to prevent me coming.