狀語(yǔ)從句：
時(shí)間狀語(yǔ)從句
引導(dǎo)詞：when，while，as，after，before，since，until，as soon as，before，after.
When you think you know nothing, then you begin to know something.
地點(diǎn)狀語(yǔ)從句
where，wherever引導(dǎo)。地點(diǎn)狀語(yǔ)從句與定語(yǔ)從句的區(qū)別，where引導(dǎo)定語(yǔ)從句時(shí)，從句前應(yīng)有一個(gè)表示地點(diǎn)的名詞作先行詞；而狀語(yǔ)從句前則無(wú)需先行詞。
原因狀語(yǔ)從句
Tom was late because he was badly ill yesterday.
引導(dǎo)詞有because, as, since, for，seeing (that), now (that), considering (that)，in that
條件狀語(yǔ)從句
引導(dǎo)詞：if，unless，on condition that
If you want to know how old a woman is, ask her sister-in-law.
If引導(dǎo)的真實(shí)條件句，虛擬條件句條件狀語(yǔ)從句中主句使用將來(lái)時(shí)態(tài)，而從句用一般現(xiàn)在時(shí)或現(xiàn)在完成時(shí)。