Unit 3I Lead-inII Language Structures Modal auxiliaries1. would + perfect infinitive used to express “unfulfilled wish”. I would have liked to sign up, but I sprained my ankle.2. should /ought to + perfect infinitive used to express “unfulfilled obligation”needn’t + perfect infinitive expressing “unnecessary past actions ”. 1) She should/ ought to have had more oral practice during the term. 2) She needn ’t have learned all the dialogues by heart.3. may /might + perfect infinitive used to expre ss “speculations about past actions ”can /could not + perfect infinitive used to express “negative deduction about pastactions ”. 1)He may/might have gone to the library. 2) She can’t/couldn ’t have gone to the library.4. must + perfect infinitive used to express “affirmative deduction about past actions”may /might as well used with the second person pronoun expressing “suggestions ”. 1) She must have gone to the language lab. 2) You may/might as well use my bike.Preparatory Questions Directions: Recast the following sentences using the following phrases:1. “would have liked to (do)”Notice: would have liked to (do) is used with the first person to express the speaker ’s wish that was not fulfilled.1) I intended to go skating with you yesterday but I couldn ’t because my mother didn ’t let me.( Response: I would have liked to go skating with you yesterday, but my mother didn ’let me.)2) I meant to sit in on Professor Wang’s class this morning but I didn ’t because I had an important meeting to attend.( Response: I would have liked to sit in on Professor Wang’s class this morning, but I had an important meeting to attend.)3) I intended to take part in the basketball match...