单项选择题 A strong，often violent，northerly wind occurring on the Pacific coast of Mexico，particularly during the colder months，is a（）.

单项选择题 A strong，often violent，northerly wind occurring on the Pacific coast of Mexico，particularly during the colder months，is called（）.

单项选择题 A stretch where the channel changes from one side of the river to the other is called a（）.