Some Dynamic Characteristics of the 2B Flare on May 16 in 1981

Some of the characteristics of the 2B flare of May 16, 1981, are discribed. 1) The filament near the flare became active long before the start of the flare. 2) A double-ribbon structure was observed and the ribbons moved apart at the velocity of 15 km/sec during the development of the flare. 3) the movement of the flare bright points found by the off-band observation and the brightening of some isolated points far from the flare formed a clear loop structure of the flares with the up-and-down movement of the flare during its development. 4) The intrusion and coverage of the flare towards the penumbra, and the umbra of the spot group were boserved.