Student or Learner
When did you join the school? is the correct answer.
How come i cannot write when did you JOINED the school?
what is wrong with the word JOINED? what tense is use in the above sentences, isnt present perfect tense?
Help needed! thanks
**Neither a teacher nor a native speaker**
I think The Parser has already written very good information.
As an addition:
"When did you join the school?" = Simple Past
Whenever it's a question or a negative sentence you will need a "do".
I did not join the school.
Did you join the school?
Did you not join the school?
When it's a positive sentence you do not need the "do".
I joined the school last year.
You can write:
I did join the school last year.
but it's not necessary.
(It's more to emphasize the sentence.)
Person 1: You did not join the school, did you?
Person 2: Sure! I did join the school!
A very important fact:
If you ask who did something, you don't need the "do":
Who joined the school?
Who enjoyed the party last night?
Who watched this movie?
If you have any other questions just ask.
(Not a teacher)
To add to what the others have said, in English, generally the first verb of a verb phrase is the tensed verb.
So, yes, the sentence is simple past, but it is the 'do' that is given the past tensing - did. This means that the 'join' doesn't need to be tensed, since the fact the sentence is past is indicated by the 'do' as 'did'.