Techniques for grouping items of vocabulary fall into three general categories: semantic fields, phonological sets and grammatical sets. Grouping items related by topics, for example, types of fruit, belongs to the semantic fields.（）

Syllables are short when they are stressed.（）

判断题Syllables are short when they are stressed.（）

The most powerful signal of stress is a change of pitch...

判断题The most powerful signal of stress is a change of pitch on the vowel.（）

Of the four possible tune movements, high fall is used ...

判断题Of the four possible tune movements, high fall is used for statements and wh-questions; high rise is used for questions asking for repetition of something; low rise is for yes/no questions, etc. and fall rise is for corrections and polite contradictions.（）