歌曲明明白白我的心:FS4,FS5 must be set correctly,or system can not boot up!是什么意思？

FS4,FS5 must be set correctly,or system can not boot up!是什么意思？ what must be must be!什么意思！ must be是什么意思 can be,may be和must be You must be home at ....? can be与must be 的区别 you must be a bitch是什么意思`` I must be off什么意思呢? IP address must be specified 是什么意思?/ He must be a teacher,_____?