Simplify the following text for a Grade 10 native English-speaking person.
Original: The lymphatic system is a complex network of lymphoid organs , lymph nodes , lymph ducts , lymph tissues , lymph capillaries , and lymph vessels that make and transport lymph fluid from tissue to the circulatory system .
Simplified: Lymph nodes are located at intervals along the lymphatic system . Several afferent lymph vessels bring in lymph , which percolates through the substance of the lymph node , and is drained out by an efferent lymph vessel .