*\input basic\hsize 4 in\input story
! Blank space should follow file name.
<to be read again> 
                   \hsize 
(*) \input basic\hsize
                       4 in\input story
↑
 (basic.TEX 1 2 3 4) (story.TEX 1 2
! You can't do that in horizontal mode.
p.2,l.16 properly. \end
                       
↑
 [1])
*\hsize 3 in \input story
 (story.TEX 1 2
! You can't do that in horizontal mode.
p.2,l.16 properly. \end
                       
 [2])
*
*\hsize 1.5 in \input story
 (story.TEX 1 2
Overfull box, 9.3728 points too wide:
\hbox( 9.3333 + 1.9444)x 108.4050, glueset-1.0000
.\:a a
.\glue 3.3333 plus 1.6667 minus 1.1111
.\:a d
.\:a i
.\:a s
.etc.
Overfull box, 18.2617 points too wide:
\hbox( 6.9444 + 1.9444)x 108.4050, glueset-1.0000
.\:a t
.\:a h
.\:a e
.\:a r
.\:a e
.etc.
! You can't do that in horizontal mode.
p.2,l.16 properly. \end
                       

Overfull box, 5.6691 points too wide:
\hbox( 6.9444 + .0000)x 108.4050, glueset-1.0000
.\hbox( .0000 + .0000)x 20.0000
.\:a M
.\:a r
.\:a .
.\glue 4.4444 plus 5.0000 minus .3704
.etc.
Overfull box, 17.1506 points too wide:
\hbox( 6.9444 + 1.9444)x 108.4050, glueset-1.0000
.\:a c
.\:a a
.\:a l
.\:a l
.\:a e
.etc.
Overfull box, 4.0395 points too wide:
\hbox( 6.9444 + 1.9444)x 108.4050, glueset-1.0000
.\:a t
.\:a i
.\:a n
.\:a g
.\:a ,
.etc.
Overfull box, 13.5395 points too wide:
\hbox( 6.9444 + 1.9444)x 108.4050, glueset-1.0000
.\:a h
.\:a e
.\glue 3.3333 plus 1.6667 minus 1.1111
.\:a g
.\:a a
.etc.
Overfull box, 27.7061 points too wide:
\hbox( 6.9444 + 1.9444)x 108.4050, glueset-1.0000
.\:a t
.\kern-.2778
.\:a y
.\:a p
.\:a i
.etc. [3])
*\jpar 1000 \input story
 (story.TEX 1 2
! You can't do that in horizontal mode.
p.2,l.16 properly. \end
                       
 [4])
*\ragged 1000 \input story
 (story.TEX 1 2
! You can't do that in horizontal mode.
p.2,l.16 properly. \end
                       
 [5])
*\hsize 1 in \input story
 (story.TEX 1 2
! You can't do that in horizontal mode.
p.2,l.16 properly. \end
                       

Overfull box, 15.1374 points too wide:
\hbox( 6.9444 + .0000)x 72.2700, glueset-1.0000
.\hbox( .0000 + .0000)x 20.0000
.\:a M
.\:a r
.\:a .
.\glue 4.4444 plus 5.0000 minus .3704
.etc. [6])
*\end