曲折 (qū zhé): winding; (fig.) complicated

This mountain road is extremely winding; it took us two hours of driving to reach the summit.

The plot of this novel is full of twists and turns and deeply moving; once you start reading, you can't put it down.

Her life journey has been full of ups and downs, but she never gave up on her dreams.

The negotiation process was very tortuous; only after many rounds of communication did both sides finally reach an agreement.

Looking back, he said with emotion that although the road to success is winding, as long as you persevere, you can reach the end.