求翻译：合作学习在20世纪 70年代初兴起于美国，并在70年代中期至80年代中期取得实质性进展。这是一种富有创意和实效的教学理论与策略。是什么意思？

Cooperative learning in the early 1970s, the rise in the United States, and made substantive progress in the mid-1970s to the mid-1980s. This is a creative and effective teaching theories and strategies.

Cooperative learning in early 70s of the 20th century, and emerged in the United States in the mid-70s to mid 80s substantive progress has been made. This is an innovative and effective teaching theory and policy.

The cooperation study emerges in the 20th century the beginning of 70's in US, and makes the substantive progress in the 70's intermediate stages to the 80's intermediate stages.This is one kind of rich creativity and the actual effect teaching theory and the strategy.

Cooperative learning in the early 1970 of the 20th century the rise in United States, and in the mid-70 to 80 medium to make substantive progress. This is an innovative and effective teaching theory and policy.

正在翻译，请等待...