[Grammar] Infinitive verb + Ing form

[Tha Lita]

Does anybody know?:
I have a question: What is the difference between using the verb in the infinitive or using the verb in the infinitive form + ING? I know that the preposition TO + ING form is also used to indicate the infinitive form of the verb. For example: "What is the secret to reaching fluency in a language?" I know I should use " What is the secret to reach fluency in a language?" I also found this sentence using the same grammar pattern :"The Secrets to Developing Advanced Fluency in a Foreign Language"

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Is there any specific explanation to use the TO + Verb + ING form? I do appreciate your answer. Thanks a lot, teachers!

 

[MikeNewYork]

Does anybody know?:
I have a question: What is the difference between using the verb in the infinitive or using the verb in the infinitive form + ING? I know that the preposition TO + ING form is also used to indicate the infinitive form of the verb. For example: "What is the secret to reaching fluency in a language?" I know I should use " What is the secret to reach fluency in a language?" I also found this sentence using the same grammar pattern :"The Secrets to Developing Advanced Fluency in a Foreign Language"

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Is there any specific explanation to use the TO + Verb + ING form? I do appreciate your answer. Thanks a lot, teachers!

I think you are a bit confused. And that is OK because this is a confusing area of English. Infinitives usually appear as "to + bare verb form". The "to" is not a preposition there. We call it a particle, which is a word that has no meaning. It is a marker. The -ing form of a verb is either the present participle of the verb or a gerund, which is a verbal form acting as a noun. The present participle can be used as part of the main verb in a clause or sentence or as a modifier (adjective or adverb).

In your example, "What is the secret to reaching fluency in a language", the -ing form of the verb is a gerund (noun) following the preposition "to". So "to reaching fluency in a language" is a prepositional phrase: to + gerund (noun) + noun (direct object of the gerund) + another prepositional phrase (which modifies (fluency). Your second example is not as natural for me. If I had to analyze that sentence, I would say that "to reach" is an infinitive + noun (object of the infinitive) + prepositional phrase. The first is better in my opinion. The bottom line is that "to" as a particle or preposition can be very confusing.