雨がやんでくれたらいいのに。

rain

indicates sentence subject (occasionally object); indicates possessive (esp. in literary expressions); but; however; still; and

to cease; to stop; to be over

good; excellent; fine; nice; pleasant; agreeable; sufficient (can be used to turn down an offer); ready; prepared; profitable (e.g. deal, business offer, etc.); beneficial; OK

although; when; and yet; despite this; in spite of; even though; but even so; but even then; however; nevertheless; for all that; notwithstanding that; while; if only; I wish; I tell you; you should do; in order to