1. INFINITIVE TO-INFINITIVEBARE INFINITIVE (Infinitive without to) GERUND DO TO DO DO DOING After most verbs: (RULE) I want to dance After most adjectives She’s happy to stay To express purpose She went to London to study After most auxilary/modal verbs He should do it After some other lexical verbs: I’ll let you go He’s made me study Law Subject of a sentence Living in London is exprensive After prepositions He’s interested in singing After seeing her, he fell in love After certain verbs /expressions She denies stealing it

2. problems Some verbs are followed A) by a to-infinitive: want… B) by a bare infinitive: can… C) By a gerund : deny… D) By a gerund or infinitive: start… E) By a gerund or infinitive but with a change of meaning: forget…

3. Forms INFINITIVE GERUND present: (to) do present: doing continuous: (to) be doing perfect: (to) have done perfect: having studied continuous: (to) have been doing continuous: having been doing They should study They should be studying They should have studied They should have been studying