C, 415 bytes

#import<stdio.h>
#define A(a,c,o)for(l=strlen(a)-o,k=0;c[k];)a[l+k]=c[k++];
j,k,l;main(i){char s[999],a[999]="[",b[999]="{",c[999]="[",t[]=" ";for(;fgets(s,999,stdin);){A(b,"{",0)A(a,"[",0)for(i=0;s[i];++i){j=0;for(;s[i]-32&&s[i]-10&&s[i];++i){j=1;t[0]=s[i];A(c,t,0)A(b,t,0)A(a,t,0)}if(j){A(c,", ",0)A(b,", ",0)A(a,", ",0)}}A(c,"; ",2)A(b,"}, ",2)A(a,"], ",2)}A(c,"]",2)A(b,"}",2)A(a,"]",2)puts(a);puts(b);puts(c);}

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C, 415 bytes

#import<stdio.h>
#define A(a,c,o)for(l=strlen(a)-o,k=0;c[k];)a[l+k]=c[k++];
j,k,l;main(i){char s[999],a[999]="[",b[999]="{",c[999]="[",t[]=" ";for(;fgets(s,999,stdin);){A(b,"{",0)A(a,"[",0)for(i=0;s[i];++i){j=0;for(;s[i]-32&&s[i]-10&&s[i];++i){j=1;t[0]=s[i];A(c,t,0)A(b,t,0)A(a,t,0)}if(j){A(c,", ",0)A(b,", ",0)A(a,", ",0)}}A(c,"; ",2)A(b,"}, ",2)A(a,"], ",2)}A(c,"]",2)A(b,"}",2)A(a,"]",2)puts(a);puts(b);puts(c);}

It's a monster and waaayyyy too long, but I'm done with it. Should have gone for a different approach probably.

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C, 409 bytes

#import<stdio.h>
#define A(a,c,o)for(l=strlen(a)-o,k=0;c[k];)a[l+k]=c[k++];
j,k,l;main(i){char s[999],a[999]="[",b[999]="{",c[999]="[",t[]=" ";for(;fgets(s,999,stdin);){A(b,"{",0)A(a,"[",0)for(i=0;s[i];++i){j=0;for(;s[i]-32&&s[i]-10;++i){j=1;t[0]=s[i];A(c,t,0)A(b,t,0)A(a,t,0)}if(j){A(c,", ",0)A(b,", ",0)A(a,", ",0)}}A(c,"; ",2)A(b,"}, ",2)A(a,"], ",2)}A(c,"]",2)A(b,"}",2)A(a,"]",2)puts(a);puts(b);puts(c);}

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C, 415 bytes

#import<stdio.h>
#define A(a,c,o)for(l=strlen(a)-o,k=0;c[k];)a[l+k]=c[k++];
j,k,l;main(i){char s[999],a[999]="[",b[999]="{",c[999]="[",t[]=" ";for(;fgets(s,999,stdin);){A(b,"{",0)A(a,"[",0)for(i=0;s[i];++i){j=0;for(;s[i]-32&&s[i]-10&&s[i];++i){j=1;t[0]=s[i];A(c,t,0)A(b,t,0)A(a,t,0)}if(j){A(c,", ",0)A(b,", ",0)A(a,", ",0)}}A(c,"; ",2)A(b,"}, ",2)A(a,"], ",2)}A(c,"]",2)A(b,"}",2)A(a,"]",2)puts(a);puts(b);puts(c);}

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