text: * sec.2.2 is about label-preserving translation  and many notations are introduced.  However, it is not clear what label here refers to,  and it does not shown in the notation so far at all.  Only until the end of sec.2.2, the function F(.) is introduced and its revelation - Google Search as label function is discussed only at Fig.4 and sec.2.3. * pp.5 first paragraph: when assuming D_X and D_Y being perfect, why L_GAN_forward = L_GAN_backward = 0?  To trace back, in fact it is helpful to have at least a simple intro/def. to the functions D(.) and G(.) of Eq.(1).  * Somehow there is a feeling that the notations in sec.2.1 and sec.2.2 are not well aligned.  It is helpful to start providing the math notations as early as sec.2.1,  so labels, pseudo labels, the algorithm illustrated in Fig.2 etc. can be consistently integrated with the rest notations.  * F() is firstly shown in Fig.2 the beginning of pp.3, and is mentioned in the main text as late as of pp.5. * Table 2: The CNN baseline gives an error rate of 7.80  while the proposed variants are 7.73 and 7.60 respectively.  The difference of 0.07/0.20 are not so significant.  Any explanation for that? Minor issues: * The uppercase X in the sentence before Eq.(2) should be calligraphic X