From what I've learned, being semi lucid just means that you are aware that your lucid, but your mind still manages to fall back to sleep, making you lose control. So your lucid but you didn't do the steps to complete your lucidity. So your just stuck halfway there. Complete it.!
"Everything we see or seem, is but a dream within a dream but be that there, so true, so fair, we do not dare, the hating nightmare..."