Hi Gharbi,
Good question!
Divide and conquer, it�s the principle I use when explaining this to my students. It goes like this:
INFINITIVE WITH TO is the general rule (I want to break free I quote �they all know the song), therefore no need to study a list of verbs taking infinitive
INFINITIVE WITHOUT TO goes with modals, auxiliaries, let & make (Let it go �another well-known tune), this is easy to remember, or at least they can �play by ear� �no-one says �Can you to repeat?�, right?
GERUND is the problem. Students need to study the list of verbs taking gerund. I usually split it into 3 groups:
accept admit anticipate appreciate avoid be afraid of be sorry for be used to begin can�t bear can�t stand can�t help carry on | consider consent to continue delay deny detest dislike dread end endure enjoy excuse imagine | involve fancy feel like find finish forget give up go go on hate involve like loathe | look forward to love mention mind miss object to permit postpone practise prefer prevent propose quit | recall regret recommend remember report resent resist risk start stop suggest tolerate try |
1. The LIKE family (highlighted in yellow above),which may include a few more verbs than the classic like-love-hate
2. The START-GO ON-FINISH family (highlighted in green above)
3. The rest of the verbs in the list are harder to classify but I usually ask my students to find a �common denominator�: imagine-propose-suggest are often linked around the concept of �having and sharing ideas� but what about miss, or involve? Well, tough luck -these are the ones they have to study! But then it�s not such a long list now, is it?
Obviously there are also strange verbs: perhaps the most unusual ones are those you mentioned: verbs taking to + gerund (look forward to, be used to, admit/object to) � My way round this is that these verbs really take a noun
I�m used to cold weather
I�m used to sport
but failing that they will take an ING form acting as a noun
I�m used to getting up early
I�m used to swimming
Plus, there are verbs with a different meaning when using infinitive or gerund (stop-remember-regret-forget-need-try) and verbs that can use both, with very little or no difference (start, like)� , but perhaps that is next lesson?
Hope that helped!