use strict and warnings belong inside a Perl file. For example, you can create a file named "foo.pl", give it execute permissions, and add these 2 lines at the top:

use strict;
use warnings;
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Tutorials -> Getting Started with Perl

You're not actually executing a Perl script. There are several ways to invoke a Perl script. One would be, perl scriptname at your command prompt, assuming paths are set up appropriately. Another would be to invoke the script name itself, assuming you're using an OS where a file can be made executable. In that case the shebang line would direct the OS to use the Perl interpreter on the rest of the file.

perlrun will help you understand how to invoke a Perl program.

As someone already mentioned, what you're doing is trying to run a program named "use." There's no script presented in anything you did. That sort of begs the question, "What has to happen next?" The answer is probably execute your Perl script. A module alone isn't sufficient.

So you either have to use perl's command line switch to run code from the command line like so:

perl -e 'your code goes here' 
perl -E 'your code goes here' # This enables Perl 5.10 features
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Or you have to create a Perl script as toolic and Davido have already mentioned. For example:

#!/usr/bin/perl
use feature ":5.10"; # Use all new features in Perl 5.10
use strict;
use warnings;   
# Your code goes here here
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Well, you can enter your script right ahead from the command line, but with no chance to edit previous lines:

$ perl
print "Hello world\n";
^D
Hello world
$
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That's getting really nitpicky!! :-) It certainly doesn't offer the typical UNIX shell-like experience the OP seemed to expect. And the commands are not interpreted line by line.

Elda Taluta; Sarks Sark; Ark Arks

There are a couple options for a Perl CLI (command line interpreter) - Adam Kennedy's Perl::Shell might be one to try.