如何使用贝壳网教学资源

Unit 1 Part A

Unit 1 Part B

Unit 1 Part C

Unit 2 Part A

Unit 2 Part B

Unit 2 Part C

Unit 3 Part A

Unit 3 Part B

Unit 3 Part C

Unit 4 Part A

Unit 4 Part B

Unit 4 Part C

Unit 5 Part A

Unit 5 Part B

Unit 5 Part C

Unit 6 Part A

Unit 6 Part B

Unit 6 Part C