Practical experience suggests that interference from the mother tongue is the only or major source of errors.
A.正确 B.错误正确答案F
Practical experience suggests fat interference from the mother tongue is not the only or major source of errors, One stu y shows that only 3 per cent of subjects'ermors could be classified as interference crrors, whiie 85 per cent errors were developmental errors.
评分标准：答对得2分；答错扣2分。解释不当，酌情扣分。
