校园卡
campus card
Talk about a lost campus card with `下去`, separable verbs, duration complements, and time expressions with `以前/以后`.

Look for a lost campus card and decide what to do before and after class.
Practice the words that carry this lesson's dialogue, patterns, and final question.
`下去` can mean an action or state continues from now.
For separable verbs like `游泳`, a duration usually goes between the two parts.
Use `以前` for before a time or event, and `以后` for after it.
Separable verbs do not behave like normal verbs.
Do not put an object directly after a separable verb. Say `游了半个小时泳`, not a direct object after `游泳`.
Choose the separable-verb sentence.
Which sentence is natural?
Choose the before/after sentence.
Which sentence uses `以前` correctly?