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At the 50-year point, it is perhaps a good time to revisit the nature of turbulent fluidization with some possible new interpretations. Different transition velocities to TFB regime based on various measuring techniques and criteria especially developed after 2000 will be reviewed. The flow mechanisms and the interactions between the dilute bubble/void phase and the dense particulate phase will be discussed based on both the time average data such as the overall pressure drops or the solids holdups and the instantaneous signals such as the time series analysis of signals or images. The two-phase flow structure which is well accepted in bubbling flow regime will be examined and extended in the turbulent regime to reveal the link between the conventional flow regimes. More quantitative analysis on the dynamic behavior of both the gas bubbles/voids and particles will be reviewed and the spatial heterogeneity of flow structure will be discussed.