1) Derivational suffixes are groups of letters that are attached to a word to form or derive a new word. 
Example: suffix "-ation", noun base: flirt. new word: flirtation.

2) Predicate determines the nature of the argument. In a sentence, a word that functions as a verb is a predicate. 
Example: I am sleeping. Subject - I ; predicate - am sleeping.

3) Open and close questions. 
Open questions are questions that needs elaboration or further explanation. They require the respondent to think and reflect, give feelings and opinions, and control of the conversation is in the hands of the respondent. 
Close questions are questions that can be answered by one word or a short phrase. They give you facts, are easy and quick to answer, and control of the conversation is with the questioner. 
4) Falling tone is a tone that is usually regarded as neutral. It gives an impression of finality.                                                              hope i help you