... discovered how to open the safe 2. I showed her which button to press 5. PHRASE OF PURPOSE : Ex: 1. He tried to study hard in order to / so as to/ to pass every exam 6. NOUN + TO INFINITIVE ( replace ... be able to use some structures containing infinitives with and without to appropriately. II. Teaching aids. Textbook, handouts.. III.Procedure. A. BARE INFINITIVE. 1. MODAL VERBS + BARE INFINITIVE ... must do/ to do 2. She is always the last to go/ who goes * NOTES : ... FOR + OBJECT + TO INFINITIVE Examples 1. It’s difficult to do this exercise. This exercise is difficult for me to do . ...