【1】The population of Shanghai is larger than that of Wuhan. 上海人口比武汉人口多。

备注:替代词that指代前面提到的名词the population, that of Wuhan=the population of Wuhan

【2】The military budget of that year is thirty times as large as that of 1950. 那年的军事预算是1950年的30倍。

备注:替代词that指代前面提到的名词the military budget, that of 1950=the military budge of 1950

【3】One of her favourite sounds is that of a kettle singing on the hob.【属于下面第4种特指同类异物用法】

备注:替代词that指代前面提到名词the sound, that of a kettle singing on the hob.=the sound of a kettle singing on the hob.

 关于one/ones/the ones/that/those用法区别如下供网友参考

【一】代词one用来替代表泛指的单数名词(泛指同类异物单数)，相当于a/an+单数可数名词
Two heads are better than one. 两人智慧胜一人。
I lost my old camera;this is a new one. 我的旧相机丢了，这是一架新的。

【二】代词ones用来替代表泛指的复数名词(泛指同类异物复数)，通常用 ones。

Hard beds are healthier than soft ones. 硬板床比软床有利于健康。
Green apples often taste better than red ones. 青苹果往往比红苹果好吃。
We can lend you plastic chairs or metal ones. 我们可以借给你塑料椅子或者金属椅子。

【三】the ones替代表特指的复数名词(特指同类异物复数)，通常用 the ones。
I’d like to try on those shoes. The ones at the front of the window.我想试试那双鞋子。橱窗里前边的那一双。

Are they the ones who moved here recently?是最近搬到这儿来的那些人吗?

Don’t buy the expensive apples and you can get the cheaper ones.别买那价钱贵的苹果，你可以买那便宜的。

【四】代词that替代不可数名词/可数名词单数，尤其是带有后置定语/后置修饰语为 of/in介词短语，用 that替代前面名词。

The weather of Beijing is colder than that of Guangzhou. 北京的天气比广州冷。

The weather of Beijing is as good as that of Shanghai . 北京的天气和上海天气一样好。

The population of China is much larger than that of Japan. 中国人口比日本人口多得多。

A grandparent’s job is easier than that of a parent.祖父母的任务比父母的任务要轻松一些。

The engine of your car is better than that of mine.你汽车引擎比我汽车引擎要好。

【五】 those 来替代表特指的复数名词(特指同类异物复数)，尤其是当其后有 of /in引导的介词短语作后置定语。

Waves of red light area bout twice as long as those of blue light.红色光线的波长约为蓝色光线波长的两倍。

The bikes made in China are as good as those made in the USA.中国生产自行车和美国生产自行车一样好。

The houses of the rich are generally larger than those of the poor.富人的房子通常比穷人房子大。

His ideas are little different from those of his friends. 他的想法和他朋友的想法没什么两样。

备注：在英语语言中，为了避免前面的名词在后面再次出现，所以使用各种各样代词进行替代。