Complex sentence: In 1937, the Primary state highways were established and State Road 4 became (PSH 4), while the former Candian branch became Secondary State Highway 4A (SSH 4A) and another highway, extending from Lind to Wilbur, became SSH 4B.
Split into simpler sentences: In 1937, the Primary state highways were established and State Road 4 became (PSH 4), while the former Canadian branch became Secondary State Highway 4A (SSH 4A). Another highway, extending from Lind to Wilbur, became SSH 4B.