Abstract: The nuclear reaction at energies near the Coulomb barrier is an effective way to study the interaction between nuclear structure and dynamics. As more exotic weakly bound nuclei become accessible at new accelerator facilities, it is becoming critically important to understand the influence of weak binding energy on reaction dynamics, including on fusion. At present, a large number of experiments have shown that the complete fusion cross section between stable weakly bound nuclei such as ^{6, 7}Li, ⁹Be and heavy mass target nuclei is suppressed about 30% lower than the fusion cross section calculated by existing theoretical models and the fusion cross-section derived from tightly bound nuclear systems. In order to investigate the breakup effect of weakly bound nuclei on the suppression of the complete fusion cross section, studying the breakup reaction and mechanism of weakly bound nuclei has become concerned. Currently, research groups both domestically and internationally have conducted studies on the breakup reactions of weakly bound nuclei by coincidence measurement. It is concluded that the suppression of the above-barrier complete fusion cross section of the weakly bound nuclei is mainly caused by the prompt breakup of the projectile-like nuclei formed through the transfer of the weakly bound nuclei, and the relative contributions of different breakup channels to the suppression of the complete fusion were obtained. Our research group has also conducted experiments on the breakup mechanism of ^{6, 7}Li+²⁰⁹Bi based on a large solid-angle coverage array. The beam energies were set at 30, 40, and 47 MeV. We successfully identified the components of prompt breakup and resonant breakup for the α+α, α+t, α+d, and α+p breakup channels. For the first time in the ⁶Li+²⁰⁹Bi experimental data, the α+t break-up channel was observed, further refining the understanding of the break-up reaction mechanism for ^{6, 7}Li+²⁰⁹Bi.