Keyword string {

##</code><code>##

Keyword 1_string { 

##</code><code>##

Keyword string {

Keyword 
string {

Keyword string 
{

Keyword 
string 
{

#string could also be in double quotes

Keyword "string" 
{

##</code><code>##

foreach (<>) {
    s/Keyword\s+\"*([\S"]+)\s+/Keyword 1_$1 /;
    print;
}