Children’s first words may bear little resemblance to adult forms (/ga/ for squirrel), and they may at first produce multiple versions of words. Mastering adult pronunciations takes time and practice. Babbling allows practice with some sounds, but those sounds may only appear in words years later. Early vocalizations, at times paired with gestures, often precede recognizable words. And children take time before they can produce versions that match adult productions. Some 70% of children’s words up to age four are inaccurate and variable in form. Children may select some word forms over others in production because they are easier targets. They simplify words by substituting sounds they can manage; they assimilate some sounds to neighboring ones; they omit some sounds, especially in clusters. And they may set up templates for multisyllabic words, focussing on stressed syllables over unstressed ones. As they get older, they make spontaneous repairs to words that don’t match their stored representations, and also repair when asked by others. Finally, they practice words, to themselves, and in their daily language use. Single words are easier than word combinations, so longer utterances take still more practice.