It is really a matter of learning which verbs take 'to-infinitive' clauses and which take an '-ing' clause, Claudia. After some verbs, e.g. 'tell', 'advise', 'ask', 'to-infinitive' follows the object: ...

While educated people agree on most grammatical rules, there are fierce debates on a few key points. We're going to lay down the most controversial rules and explain when to follow them and when to ...