A method of forming a three-dimensional object, comprising: providing a carrier and an optically transparent member having a build surface, said carrier and said build surface defining a build region therebetween; filling said build region with a polymerizable liquid, said polymerizable liquid comprising a mixture of (i) a light polymerizable liquid first component, and (ii) a second solidifiable component that is different from said first component, intermittently irradiating said build region with light through said optically transparent member to form a solid polymer from said polymerizable liquid first component, continuously or intermittently advancing said carrier away from said build surface to form said three-dimensional object from said solid polymer, wherein said intermittently irradiating comprises alternating periods of active and inactive illumination, wherein the average duration of the periods of active illumination is less than the average duration of the periods of inactive illumination, and concurrently with or following the forming of said solid polymer, solidifying and/or curing said second solidifiable component to form said three-dimensional object, wherein: (a) said solidifying and/or curing step is carried out concurrently with said irradiating step and: (i) said solidifying and/or curing step is carried out by precipitation; or (ii) said irradiating step generates heat from the polymerization of said first component in an amount sufficient to thermally solidify or polymerize said second solidifiable component; and/or (b) said solidifying and/or curing step is carried out subsequent to said irradiating step and is carried out by: (i) heating said second solidifiable component; (ii) irradiating said second solidifiable component with light at a wavelength different from that of the light in said irradiating step; (iii) contacting said second solidifiable component to water; and/or (iv) contacting said second solidifiable component to a catalyst. providing a carrier and an optically transparent member having a build surface, said carrier and said build surface defining a build region therebetween; filling said build region with a polymerizable liquid, said polymerizable liquid comprising a mixture of (i) a light polymerizable liquid first component, and (ii) a second solidifiable component that is different from said first component, intermittently irradiating said build region with light through said optically transparent member to form a solid polymer from said polymerizable liquid first component, continuously or intermittently advancing said carrier away from said build surface to form said three-dimensional object from said solid polymer, wherein said intermittently irradiating comprises alternating periods of active and inactive illumination, wherein the average duration of the periods of active illumination is less than the average duration of the periods of inactive illumination, and concurrently with or following the forming of said solid polymer, solidifying and/or curing said second solidifiable component to form said three-dimensional object, wherein: (a) said solidifying and/or curing step is carried out concurrently with said irradiating step and: (i) said solidifying and/or curing step is carried out by precipitation; or (ii) said irradiating step generates heat from the polymerization of said first component in an amount sufficient to thermally solidify or polymerize said second solidifiable component; and/or (b) said solidifying and/or curing step is carried out subsequent to said irradiating step and is carried out by: (i) heating said second solidifiable component; (ii) irradiating said second solidifiable component with light at a wavelength different from that of the light in said irradiating step; (iii) contacting said second solidifiable component to water; and/or (iv) contacting said second solidifiable component to a catalyst. (a) said solidifying and/or curing step is carried out concurrently with said irradiating step and: (i) said solidifying and/or curing step is carried out by precipitation; or (ii) said irradiating step generates heat from the polymerization of said first component in an amount sufficient to thermally solidify or polymerize said second solidifiable component; and/or (i) said solidifying and/or curing step is carried out by precipitation; or (ii) said irradiating step generates heat from the polymerization of said first component in an amount sufficient to thermally solidify or polymerize said second solidifiable component; and/or (b) said solidifying and/or curing step is carried out subsequent to said irradiating step and is carried out by: (i) heating said second solidifiable component; (ii) irradiating said second solidifiable component with light at a wavelength different from that of the light in said irradiating step; (iii) contacting said second solidifiable component to water; and/or (iv) contacting said second solidifiable component to a catalyst. (i) heating said second solidifiable component; (ii) irradiating said second solidifiable component with light at a wavelength different from that of the light in said irradiating step; (iii) contacting said second solidifiable component to water; and/or (iv) contacting said second solidifiable component to a catalyst.