[not needed anymore- removed by CK]
I think that linking the sentences with the same language is the correct answer. Another argument in favour of linking phrases of the same language would be the (future) task of finding the duplicate and similar phrases, because there definitely will be a numerous pairs of a little bit different punctuation, or different wording of the same proverb etc.
When the tags on the links are available, it would be much more flexible, as one would be able to specify not only "equivalent" links, but also "similar", "related to", "not equal to" and other kinds of links.
But while the tags on the links are impossible, I think it is the correct solution to use existing links to connect reworded phrases, even in the same language.
Maybe we should consider a system of grades.
A certain set of members could be given the right to set a note (say, from 0 to 10) indicating how often they would employ a sentence in their daily life.
In your example, "I like to read" would be given a 7 when "I like reading" would score 9, giving a foreigner a good idea on which one is the most used.
What do youse think ?
It seems like around here (Northeastern U.S.), things like "I like to read" are more common. There seems to be a subtle semantic difference that I have never heard anyone mention. "I like to read" emphasizes the general idea of reading, whereas "I like reading" emphasizes the physical action of it. Maybe this is just a regional thing? I don't know.
Hmm I'm not sure this would work because of what Zifre has already said: an expression may be very used in one zone/country, and not in another (for example: differences between British and American English, Canadian French and French from France, Spanish from Spain and from Argentina...) That's why I'd feel reluctant to giving marks to the sentences, because maybe an expression, word, sentence sounds weird in Spain, but it may be an everyday expression in Peru.
Just add a new sentence and link to it in a comment.
As far as I'm concerned, I'm okay with linking the examples you mentioned:
Yesterday I went to school. = I went to school yesterday.
I like to read. = I like reading.
I'm not too sure about linking modern sentences to archaic sentences though, or natural to unnatural-sounding sentences. When I think about it, it seems that linking sentences is not just about meaning but also about the effect generated by the sentence. You need to ask yourself "If I said this other sentence to a native speaker, would it have the same effect as the original sentence?"
When you say "I like to read", it pretty much has the same effect as "I like reading", so it can be linked safely.
But when you say "'Sup man?", it definitely doesn't have the same effect as "How are you, sir?".
When you speak like Yoda it doesn't have the same effect as when you speak with more commonly accepted grammar.
And technically, "You look fantastic" could have the same meaning as "You look awful" if the former statement was sarcastic.
In the end it's up to the contributors to decide if two sentences are close enough to be linked or not, but it would make things confusing if we opted to link only based on meaning.