1) 指示代詞形式：
(1) this/that及其復(fù)數(shù)形式these/those，用于指代名詞、短語和句子。
(2) same/such沒有性，數(shù)，格的變化。
(3) so沒有性，數(shù)，格的變化。
2) 指示代詞句法作用：
(1) this/these和that/those的用法：分別用于在空間和時間上的進(jìn)指和遠(yuǎn)指。
�、� 作為先行詞用法的that和those中，those能指人和物，that 只能指物，且表單數(shù)。
② that/those，this/these可用來替代前文明確的名詞及名詞短語。
�、� This和that可以作為狀語表示程度。
注：one表示泛指，that和it 表示特指。that與所指名詞為同類，但不是同一個，而it 與所指名詞為同一個。
The hat you bought is bigger than that I bought.
I can't find my hat. I think I must buy one.
I can't find my hat. I don' t know where I put it.
(2) such，(the)same的用法
二者單復(fù)數(shù)相同，在句中可做主語、賓語、表語和定語。
Such was my immediate impression.
She said the same thing all over again
His illness was not such as to cause anxiety.
(3) so的代詞用法：只用于兩種情況
① believe，expect，hope，suppose，think，do等表示看法，假設(shè)和行為的動詞之后，代替上文一個肯定陳述句。
�、� 用于系動詞之后，替代表語。
Eg: Are you going to play football tomorrow? I hope so.
He is a lazy boy and will always be so.
