“…In the second example, we select γ 1 (t) = 1, γ 2 (t) = 1, γ 3 (t) = β, a 0 = −2 α + β 2 , k 1 = 4, l 1 = −2 and set the integration constants of (3.16) and (3.17) as −θ 13 /6 √ 2, then the one-soliton solutions (3.18) and (3.19) give the known solutions [27] where A and B satisfy the constant-coefficient AKNS equations In view of (2.11) and (3.1), we reduce (3.2) and (3.3) as In the procedure of extending Hirota's bilinear method to (1.1) and (1.2), one of the key steps is to reduce (1.1) and (1.2) to the bilinear forms (2.9) and (2.10) by the transformations (2.7), (2.8) and (2.11). It is graphically shown that the dynamical evolutions of one-soliton solutions (3.18) and (3.19), two-soliton solutions (3.20) and (3.21), three-soliton solutions (3.22) and (3.23) possess time-varying amplitudes as Serkin et al [37][38][39] reported in the process of propagations.…”