One of the hardest parts of English grammar for second language learners (and their teachers!) is the constructions V V-ing and V to V, exemplified by ‘I like eating pizza’ and ‘I want to eat pizza’. It is also possible to say ‘I like to eat pizza’, but not ‘I want eating pizza’ or ‘I like eat pizza’, ‘I want eat pizza’ and ‘I want to eating pizza’.
The form of the second verb is determined by the first verb. There are many lists of verbs which take V-ing and verbs which take to V (and those which take both – either with the same meaning or a difference in meaning), but I haven’t found anything which explains, or even attempts to explain, the difference. Michael Swan (Practical English Usage) spends 25 pages discussing the various usages of these forms, then says ‘Unfortunately, there is no easy way to decide which verbs, adjectives and nouns are followed by -ing forms, and which are followed by infinitives. It is best to check in a good dictionary.’
My current textbook lists as taking to V: decide, forget, hope, learn, need, offer, plan, pretend, promise, remember, start, try, want, would like; and as taking V-ing: enjoy, finish, go on (=continue), hate, like, love, don’t mind, spend (time), start, stop, feel like. Is there any rhyme or reason to those lists? Well, sort of. As the students were completing the worksheet, I started to sort/started sorting (nb!) the verbs in each list into groups. The verbs in the first list are generally concerned with thinking (decide, plan, learn, remember, forget), saying (offer, promise), doing (try, pretend) and (for the want of a better word) necessity (need, want, would like, hope (to which I would add have and have got)) and those in the second are generally concerned with feelings (love, enjoy, like, feel like, don’t mind, hate) and time (start, continue, go on, spend (time), stop, finish).
But this preliminary sorting doesn’t explain why those verbs take those verb forms, or why start takes both, or why some verbs, like stop, take both but with a change of meaning (start smoking = start to smoke v stop smoking =/= stop to smoke) (that last point was not covered at the level I am currently teaching).
There are further complications, which I might explore sometime, but this will do for a start. [Update 27 Nov: just for a start, the first word on the next list I found was ‘consider’, which is definitely about thinking, so one might expect ‘I considered to do something’, but no, it’s definitely ‘I considered doing something’.]