[译] 你周末干了什么？
[误] What did you do at the weekend?

[正] What did you do at weekend?
[注] “在周末”应为 at weekend，这是惯用语，weekend 前不可以加定冠词。另外，要表示“在这个周末”，习惯上用 this weekend 而不说 at this weekend；要表示“在整个周末”，习惯上说 over the weekend，不说 in all the weekend。