Simplify the following text for a Grade 9 native English-speaking person.
Original: In the USA ( and sometimes in Britain ) the season is regarded as beginning at the solstice and ending on the following equinox â '' in the Northern Hemisphere , depending on the year , this corresponds to the period between 21 or 22 December and 20 or 21 March .
Simplified: In the Northern Hemisphere the winter solstice is usually December 21 or December 22 .