What are the criteria for vocabulary selection in the Oral Approach and its significance in syllabus design in foreign language teaching?

What are the criteria for vocabulary selection in the Oral Approach and its significance in syllabus design in foreign language teaching?

ACCORDING TO PALMER,WORDS ARE CHOSEN FOR THE FOLLOWING CRITERIA:1) MOST FREQUENTLY USED BY NATIVE SPEAKERS2)ALL THE STRUCTUAL WORDS3)MOST USEFUL IN EXPLAINING THE MEANING OF OTHER LESS FREQUENTLY USED WORDS4)WORDS WHICH ARE USEFUL BECAUSE OTHER WORD CAN BE BUILT FROM THEMTHIS EFFORT TO INTRODUCE A SCIENTIFIC RATIONALE FOR SELECTING THE VOCABULARY CONTENT OF LANGUAGE COURSE REPRESENTED THE FIRST ATTEMPT TO ESTABLISH PRINCIPLES OF SYLLABUS DESIGN IN FOREIGN LANGUAGE TEACHING.