You'll be shown two techniques for whistling: one that uses your fingers, and another that doesn't. Say it's raining, your arms are full of shopping bags, and you need to flag a taxi. This no-hands whistle will allow you to emerge victorious in this situation and others. But the fingerless whistle is a little trickier to master, so you should practice the fingered whistle first. Just practice a little bit every day; soon pets and taxis alike will be at your beck and call.
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