Firstly, verbs are followed by either to-infinite or gerund.
1. When “to” is used as a preposition followed by a verb, the gerund form comes after “to” instead of the base form of the verb. For instance, confess, adjust, object, devote, etc. Example: He confessed to murdering his wife.
In this example a gerund comes after “to” because it is used as a preposition, these verbs are also called prepositional verbs.
2. There are some phrasal verbs that end with “to” which can also be followed by the gerund form. The most common ones are “look forward to”, “get around to”, etc. Examples: She is not looking forward to leaving school.
“Looking forward to” is a phrasal verb that always comes in a unit and is inseparable.
3. When “to” is part of the “adjective + to” group, such as “be used to”, “be addicted to”, “be committed/dedicated/devoted to”, “be opposed to”, etc.
Example: She is dedicated to helping the poor.
4. When “to” is part of the “noun + to” group, such as “addiction to”, “commitment/dedication/devotion to”, “reaction to”.
Example: Her dedication to helping the poor.
To conclude, there are few discoveries found in the above analysis. Firstly, it is found that verbs followed by “to + ing” structure that also applies to the noun form of the verbs. For example, “he confessed to murdering his wife” becomes “his confession to murdering his wife”. Similarly, adjectives followed by the “to+ing” can also apply to the noun form of the adjectives. For example, “she is dedicated to helping the poor.” becomes “her dedication to helping the poor.”
Secondly, according to Givon (1993, p.2), the stronger the semantic bond is between the two events, the more extensive will be the syntactic integration of the two propositions into a single clause. E.g. He confessed to murdering his wife. As two events are close to each other, they are strongly integrated.