【黃文昱】評論
關係代名詞(which)+不完整子句(子句內缺主詞、受詞) 關係副詞(where, when, why, how)+完整子句
【Mango】評論
interactive: 相互作用的
【Claire Win】評論
in this classes=in which=where
【Jill Chen】評論
These classes can be highly interactive, _9_ students communicate with each other and their teachers.