Thus, our objective is to learn a sentence (or pair) representation x k per task k, but take into account the correlation among related tasks.
given an input sequence x k = {w k 1 , w k 2 , ..., w k T } with length T , we aim to learn a sentence representation x k for the entire sequence as follows, x k = Encoder({w k 1 , w k 2 , ..., w k T }).