Answer: (1) Write the names of the four solar terms represented by A, B, C and D and their corresponding dates. a _ _ _ _ _ _ _ _(_ _ _ _ _ _ _)

(1) According to the schematic diagram of the earth's revolution, when the earth revolves to A, the sun shines directly at the equator, and the time is around March 2 1, which is the vernal equinox in the northern hemisphere; When the earth revolves around B, the sun shines directly on the Tropic of Cancer around June 22nd, which is the summer solstice in the northern hemisphere. When the earth revolves to point C, the sun shines directly at the equator, about September 23, which is the autumn equinox in the northern hemisphere; When the earth revolves to D, the sun shines directly on the Tropic of Capricorn around 65438+February 22, which is the winter solstice in the northern hemisphere.

(2) When the revolution of the earth reaches point B, the sun shines directly on the Tropic of Cancer, which is the summer solstice in the northern hemisphere. At this time, the arctic circle has extreme days, while the northern hemisphere has long days and short nights.

(3) The revolution direction of the earth is from west to east.

So, the answer is: (1) vernal equinox; 3; 2 1; Summer solstice; 6; 22; Vernal equinox; 9; 23; Solstice of winter; 12; 22; (2) Tropic of Cancer; Extreme day; The days are long and the nights are short; (3)