A：可能存在语法错误
B：存在批注
C：可能存在拼写错误
D：进行了自动更正
When he was running after his brother, the boy lost his ___ and had a bad fall.
It will _____ cold in Harbin. （ ）
做镁条燃烧实验时，用于夹持镁条的仪器是（ ）
