In general, we use: at for a POINT, in for an ENCLOSED SPACE, on for a SURFACE.
Prepositions of place describe the position of a person or thing in relation to another person or thing.
Prepositions form a small but very important word class. We use prepositions very frequently. In fact, the prepositions to, of, in, for, on, with, at, by, from are all in the top 25 words in English.
There is one very simple rule about prepositions. And, unlike most rules, this rule has no exceptions.
Prepositions are very common words. Seven of them are in the top 20 words in English. Prepositions link a word to another part of the sentence and tell us what the relationship is, for example in space or time.
These are the most common fifty irregular verbs in the English language. This does not include the auxiliary verbs "do" and "have". Just by learning these fifty, your students will have prepared themselves for 87% of irregular verb use in English!
Irregular verbs often cause problems for students of English. Here is a list of irregular verbs in English.