你猜到了开头却猜不到结局
You guessed the beginning,yet failed to guess the ending/outcome.
参考资料：
我梦见我的意中人会驾着七色云彩来娶我,我猜到了这个开头,却猜不到这个结局.
"I dreamed my lover will sail seven -color clouds to marry me ,I guess this beginning ,have not guessed the outcome ."