在電腦開不到minecraft ( 15點)

Maybe is operating system is too old to start minecraft forge 1.8 or your minecraft forge installation has corroupt. To solve your problem, try to install the same forge version and minecraft in a another computer and see how it works. Also, try to reinstall it by downloading from forge's offical page.

2015-07-23 21:53:53 補充：
Also, try to use a computer that is using windows 7 to try

Also, try to use a computer that is using windows 7 to try