How to use preposition "to" , infinitive "to" and "---ing"?

Question

When I was taking my examination, I 'learned' a new word, but I don't know how to use it. I don't know if the to following the word is a preposition. If it is then I should say "to doing". Or if to is part of the infinitive infinitive - then I should say to do. In other words: "to do" or "doing": are there any rules?

For example in "suggest doing something" why not use an infinitive? Why do we tend to say "object to doing" rather than "object to do"? I am sorry that maybe there's something wrong with my expression - but I would be grateful if you would like to help me.

Answer 1

Many prepositions usually come before a noun. We usually use the --ing form of verbs after prepositions which come before nouns. Some examples of prepositions like this are: in, on, at, about, of, up and to. Here are some examples of sentences with prepositions plus --ing:

• I succeeded in passing my exams
• I am keen on dancing.
• I am good at cooking.
• I am mad about jogging.
• I tire of reading very quickly
• I gave up smoking.
• I object to working.

Some verbs about liking/enjoying activities and also not liking/not enjoying activities usually take --ing forms of the verb:

I like shopping I hate shopping I love shopping I don't mind shopping I enjoy shopping I detest shopping I loathe shopping I adore shopping

Some other verbs also take --ing form. The best way to learn them is to learn the verbs in a sentence, not just as one word:

• I loathe shopping.

Sometimes we know that there is a to after a particular verb. We don't always know whether to is a preposition or whether it is part of another verb phrase, for example 'to swim':

• want to [verb]
• object to [verb]

There is an easy way to test whether to is a preposition or part of another verb. We can use a noun after the verb that we want to test:

• I want bananas. (no to)
• I object to bananas. (still has to)

In the first example, the word to disappeared. This shows that it belongs to another verb. It belongs to an infinitive. When there is no verb after want, there is no to. In the example with object, we still have the word to. This shows that it is a preposition. We still use the preposition when it comes before a noun.

Now we know that want must be followed by to + infinitive and object to must be followed by --ing (because to here is a preposition):

• I want [to smoke].
• I object to [smoking].

Hope this is helpful!

Answer 2

By itself "to doing" is not a valid English construction. Sometimes, 'to V-ing' is part of a larger phrase. In the sentence "My boss is used to doing all the company's taxes," the full construction is "be used to V-ing."

It means the subject is accustomed to that activity. Other examples:

• I am used to swimming in the ocean.
• She is used to riding horses.
• They were used to holding garage sales in the fall.

An infinitive is only the word 'to' followed by the basic form of a verb: 'to do', 'to be', 'to go', etc.

Maybe you've heard of gerunds? Gerunds are a part of speech made up of -ing verbs (present participles) that we treat like nouns. Most activities are gerunds. In the sentence "I like cake," 'cake' is a noun. Although 'run' is a verb, in the sentence "I like running," 'running' is a noun.

In conversational English, when suggesting an activity, we might ask, "How about watching a movie?" instead of asking "Do you want to watch a movie?" In those questions, 'watch' is a verb, and 'watching' is an activity/gerund.