the first day of the summer season is the day of the year when the Sun is farthest north (on June 20th or 21st). This day is known as the Summer Solstice.
In the United States and the rest of the northern hemisphere,
所有跟帖:
• 问的是春天和秋天。 -CirrusCloud- ♀ (0 bytes) () 09/17/2015 postreply 20:51:19
• 按严格定义,春夏一样,秋冬一样 -shadowboxer- ♂ (0 bytes) () 09/17/2015 postreply 20:58:11