Verbs can be followed by an infinitive (with or without 'to'), a gerund (-ing), a noun or a 'that' clause:
Some verbs are only followed by a gerund and some verbs are only followed by an infinitive.
Some verbs can be followed by either a gerund or an infinitive and there is little or no change in meaning. However, some verbs can be followed by either a gerund or an infinitive and there is a change in meaning.
Although each verb is different, some verbs share similarities. Thus, while you can study most examples in a dictionary, you must learn the rules for the most common verbs: see Language Practice for First, unit 23.