crystal report formula field display all fields as in data structure

Hi
I have some problem crystal report by formula field
I want to display full record with length as defined in data structure without any trims as field position get violate as there is any change in preceding field
for example

sub m1 m2 m3
11 g1 a2 a
12 a1** b1 c1
13 a b1 c2
my formula is

{table1.sub1}+" "+{table2.m1}+" "+{table2.m2}+" "+{table2.m3}
in data structure m1 has 4 character length.is it possible to print a as four letter string(a+space(3))?