第３課に戻りましょう。
tbd
Let's turn back to the third lesson.
Let's go back to lesson three.
Let's return to Lesson 3.
让我们回到第三课。
Let's go back to Unit 3.
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課， か
1. lesson
2. section (in an organization), division, department
3. counter for lessons and chapters (of a book)
tbd
に
1. at (place, time), in, on, during
2. to (direction, state), toward, into
3. for (purpose)
4. because of (reason), for, with
5. by, from
6. as (i.e. in the role of)
7. per, in, for, a (e.g. "once a month")
8. and, in addition to
9. if, although
tbd