We find it hard to present a full picture of the historical development of foreign language teaching because of scarcity of( )

What are the merits and limitations of the Cognitive Approach?

From your own experience of learning English, how should a foreign language be taught in your opinion?

What are the features of the classroom environment in the Communicative Approach?

What are the four issues related to the input hypothesis of Krashen's monitor model of second language learning theory?

What areas of language are emphasized by Oral Approach? What language skills are emphasized?

What are the function and result of the controversies in ancient Greece?

What implications does Piaget's theory of learning have for language teachers?

According to the Direct Method, What areas of language are considered more important?

Column A: Foreign Language Teaching Method

①Total Physical Response

② 2The Silent Way

③Community Language Learning

④ Suggestopaedia

⑤Three Dimensional Approach

Column B: the advocator or practitioner

a.J. Asher

b. Lozanov

c. Zhang Zhengdong

d. CharlesA.Curran

e. Gattegno

( ) is Palmer's core methodological principle.