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Existing commercial three-dimensional ( 3D ) printing systems based on powder bed fusion approach can normally only print a single material in each component .
 concept or principle: three-dimensional; concept or principle: 3D; manufacturing process: powder bed fusion; manufacturing process: print; material: material; machine or equipment: component
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: three-dimensional, 3D, powder bed fusion, print, material, component 
Answer:
 concept or principle: three-dimensional; concept or principle: 3D; manufacturing process: powder bed fusion; manufacturing process: print; material: material; machine or equipment: component