指示代词包括this， that， these， those 和such，在句子中可以作主语、定语、表语、宾语等(such不作宾语)。
that和those有时分别用来代表前面提到的不可数名词和名词复数，以避免重复。而可数名词单数往往用the one 或that one 来代替。用the one 的时候更多一些。如：
These machines are better than those we turned out last year. 生产
The oil output of this year is much higher than that of last year. 产量
The best wine is that from France。
My room is lighter than the one next door。
Ill take the seat next to the one by the window。
The film is more funny than that one。
that 可以指上面提到的事情，this指下面要谈的事情。如：
They have no time to read the books. Thats their trouble。
She was ill yesterday. Thats why she was absent。
I want to know this： How much money we have left?
What I want to say is this： Pronunciation is very important in learning English。
this 和that 有时还可以用来表示程度。如：
I dont want that much。
He is not that wise。
The book is about this thick。
