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While AM can realize many complex topologies , there still remain AM manufacturing limitations ( such as overhangs ) , which require customized TO design algorithms beyond freeform TO .
 manufacturing process: AM; concept or principle: topologies; manufacturing process: AM; material: as; engineering feature: design; concept or principle: algorithms; concept or principle: freeform
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
 Entities: AM, topologies, AM, as, design, algorithms, freeform 
Answer:
 manufacturing process: AM; concept or principle: topologies; manufacturing process: AM; material: as; engineering feature: design; concept or principle: algorithms; concept or principle: freeform