The document summarizes key points from three authors on second language acquisition: Cook, Krashen, and Freeman. Cook discusses differences between L1 and L2 learning, including factors like context and motivation. Krashen explores how the first language can interfere with L2 learning in areas like word order but notes interference is not always the case. Freeman examines L1 acquisition in babies and L2 acquisition approaches, noting affective problems can influence teenage L2 learning. The response analyzes connections between the authors and implications for teaching, such as avoiding constant error correction in early L2 learning.