concatenate string

hello gurus,

seee this example

data : var1 type string,

var2 type string,

var3 tyype string.

var1 = 'lifnr'.

var2 = '1000'.

concatenate var1 var2 into var3 .

write : / var3.

output : lifnr = 1000.

but i want to display my output as lifnr = '1000'.

through concatenate string.

thanks

anji.