How to get AWK to output 2 fields at once

[Bill Irwin]

I  have what initially seemed to be a simple requirement:  get the  first
two fields from each line in file_1, and use them as a search pattern for
GREP to extract matching lines in file_2.  Sounds simple doesn't it?  Not
for  someone with very limited knowledge of AWK!  The first pass at  this
was:

for x in `cat file_1 | awk '{ print $1 " " $2 }'`
do
        grep "$x" file_2
done

Of course, the GREP routine executed with x having the value of the first
field  of  the  first line of file_1, then with the value of  the  second
field  of  the first line of file_1, then the first field of  the  second
line, .....

Is  there a way to get AWK to output "field_1 field_2" as the value of x,
so  that  this  can be used as the search pattern for GREP,  rather  than
"field_1" "field_2" "field_1" "field_2"?
-- 
Bill Irwin    -       The Westrheim Group     -    Vancouver, BC, Canada
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