Language abrasion refers to the decline of speech behavior or speech ability in a certain language environment under the influence of linguistic or non-verbal factors (emotion, motivation, age, reduction or stop of language use, etc. ) in that language Phenomenon, with characteristics such as non-pathological, gradual, reversible and repetitive. According to the above definition, which of the following is language abrasions? ["Xiao Li's college entrance exam [weibo] English scores are good, but the English scores are not satisfactory in the opening class test after the summer break.", 'Lao Zhang in his eighties is quite different from his younger age, he often asks others to repeat what he said, and he speaks slowly.', "Xiao Zhao was sick as a child and caused deafness in both ears. Others often didn't understand what she said as an adult.", 'After middle school students go to the United States to participate in the summer camp, their English level has improved a lot.']