On time / in time, at the end / in the end

on time = at the planned time, according to the timetable or arrangement — not late. It is common with trains, buses, meetings, classes and deadlines. The opposite is late.

• The train left on time, at 8:00 exactly.

• Please be on time tomorrow. The meeting starts at nine.

• Hai is never on time. He's always ten minutes late.

in time = early enough to do something or before something happens. Two common patterns: in time for + noun and in time to + base verb. The opposite is too late.

• We got to the cinema in time for the start of the film.

• Will the package arrive in time for Tet?

• I didn't get to the station in time to catch the last train.

  = I missed the train

💡A quick test: ask “Was it late compared with the plan?” → on time. Ask “Was it early enough to do something?” → in time.

• just in time = only just early enough; a moment later would have been too late.
• in good time (mainly British) = early, with time to spare.
• in time on its own can also mean eventually, after a while — nothing to do with a schedule.
• Neither phrase takes an article: not “on the time” or “in the time” with these meanings.

• The ambulance arrived just in time.

• We left early and got to the airport in good time.

• It hurts now, but in time you'll forget about it.

at the end (of something) = at the last part of a period, an event or a place. It usually takes of: at the end of the month / the film / the class / the street. When it's clear what you mean, you can drop the of … part.

• We pay the rent at the end of the month.

• Everyone cried at the end of the film.

• Our house is at the end of the street.

  place: also at the end of

• I'll answer your questions at the end.

in the end = finally, eventually — the result after a long process, after a lot of changes, doubts or problems. It usually goes at the start or the end of the sentence, and it is not followed by of.

• We couldn't decide where to go, so in the end we stayed at home.

• The exam was really hard, but in the end I passed.

• He said he wasn't coming, but he came in the end.

💡If of follows, it's almost certainly at: at the end of the film, not “in the end of the film”. In the end stands alone and means “finally”.

In the beginning stresses “it was like this at first, and later it changed”, like at first. At the beginning of + a specific time or thing simply means its first part.

• In the beginning, living alone was hard, but now I love it.

• The rainy season starts at the beginning of May.

• At last! The bus is here.

• ✗The concert started in time, at exactly 7 p.m.

  ✓The concert started on time, at exactly 7 p.m.

  At the planned time → on time.

• ✗I didn't get there on time to see the start of the match.

  ✓I didn't get there in time to see the start of the match.

  Early enough to do something → in time to + verb.

• ✗We looked everywhere, and at the end we found the cat.

  ✓We looked everywhere, and in the end we found the cat.

  The result after a long process → in the end.

• ✗In the end of the film, the hero dies.

  ✓At the end of the film, the hero dies.

  The last part of something → at the end of.

• ✗Please be on the time.

  ✓Please be on time.

  No article.