these comparisons, we mix all training instances, order them by the size, and put them into 10 equal groups, the medium sentence lengths of which are shown.
i t i controls information from the input x i ; l t i , r t i , f t i and s t i control information from the left context cell c t−1 i−1 , the right context cell c t−1 i+1 , c t−1 i and the sentence context cell c t−1 g , respectively.