A single budgie bonded to its owner is much more likely to talk than one kept with other budgie. Males are more likely to talk than females. Teaching them is a a bit of a lottery in the sense that some birds are just more inclined to copy human speech than others, but basically it’s noticing that the bird seems especially attentive to your voice, bringing your face close to them and repeating a short phrase.
In the same way that a child learns to talk, it often takes time for their clarity to improve and ‘speech-like utterances’ are often a sign that you may have a future talker. A funny little quirk is that often a budgie will ‘practice’ when the owner isn’t around.
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