Particles #4: Use に, から, and まで to Explain When Something Occurs
から marks the starting point of an action or event. It is used similarly to "starting at" or "from" in English.
まで marks the endpoint of an action or event. It is used similarly to "until" or "to" in English.
に is used to express when something will occur. It is used similarly to "at," "on," and "in" in English.
Unlike prepositions in English, these Japanese particles always come after the time-related word, not before.
から Denotes a Starting Point
In Japanese, the particle から is used like "from" or "starting at" in English when talking about when something begins. For example, 9時から means "starting at 9:00."
Notice that, as with other particles, から comes after the word it relates to in Japanese, whereas "starting at" comes before the related word in English.
I have class starting at 8:00.
Starting today, I won't eat sugar.
まで Denotes an Endpoint
The particle まで marks the endpoint of something in Japanese phrases--as such, it is used similarly as "until" or "to," as in expressions like "from Monday to Friday".
Every week, I go to work from Monday to Friday.
No ice cream until you eat your vegetables.
に Denotes When Something Will Happen
The particle に is very versatile when used for this purpose. In English, different prepositions accompany different time words—for example, we say on Tuesday, but we also say in August and at six o'clock. In Japanese, に is used in all these cases: "on Tuesday" is 火曜日に, "in August" is ８月に, and "at six o'clock" is ６時に.
I'm going to Japan in April.
I'm going to see a movie on Friday.
Not all time expressions are marked by に—for some time words, no particle is used. Examples include 今日 (today), 来年 (next year), or 毎朝 (every morning). Exceptions like these are pretty easy to remember because the English equivalents are not accompanied by prepositions. For example, you can remember that 明日に is poor Japanese since "on tomorrow" is also poor English.
I went to Japan last April.