extracting columns using pattern file from source file

Hi experts,Please help me for the below requirement. i have a source file.(lets say contains 50 columns). I am extarcting five columns from the source file by using pattern file. for example input file:

--------a,b,c,d,"a,g","v b",s,k

outputfile

=======a,"a,g","v b",s,k

Thanks in advance subhendu

try this

$ echo 'a,b,c,d,"a,g","v b",s,k' | awk -F"," 'OFS="," {print $1,$5,$6,$7,$8,$9}'
a,"a,g","v b",s,k

awk -F, '{sub(FS $2 FS $3 FS $4,F);gsub("-","=")}1'  infile