あとでAfter; later
あとで places one action at a later time after another action or event has been completed. The two actions do not have to happen immediately one after the other.
Two events in time
The part before あとで gives the event that finishes first. The action after it happens later. A short gap is possible:
ご飯を食べたあとで、薬を飲みます。
I take my medicine after eating.
AnalyzeThe later action need not be immediate
あとで simply places the second action later than the first. Context can make the gap minutes, days, or even years.
大学を卒業したあとで、十年ぶりに先生に会いました。
After graduating from university, I met my teacher again for the first time in ten years.
AnalyzeThe ten-year interval shows that this pattern does not require immediate succession.
Why the first verb looks past
The first verb uses its plain past form because that action must be complete before the later action. This does not make the whole sentence past: the ending of the later action tells you whether the sentence describes the past, a plan, or a routine.
宿題が終わったあとで、ゲームをします。
I will play a game after I finish my homework.
AnalyzeAlthough the first verb has a plain past ending, the sentence describes a future sequence.
A loose time relation or a connected sequence?
あとで mainly says that B occurs later than A. てから more strongly presents A as the first step in a connected sequence, so it is especially natural in step-by-step instructions.
パスワードを入力してから、ログインボタンを押してください。
After entering your password, please press the login button.
AnalyzeHere, entering the password is a necessary first step before pressing the button.
More examples
仕事のあとで、友達と食事をします。
I will have a meal with a friend after work.
Analyze映画を見たあとで、感想を話しました。
After watching the movie, we talked about our impressions.
Analyze雨がやんだあとで、出かけましょう。
Let's go out after the rain stops.
Analyze授業のあとで、先生に質問してもいいですか。
May I ask the teacher a question after class?
Analyze買い物をしたあとで、家に帰りました。
I went home after shopping.
Analyzeこの本を読んだあとで、弟に貸します。
After I read this book, I will lend it to my younger brother.
Analyze