a lot of      

a lot of具有many和much的含义,所以可以用a lot of修饰可数名词和不可数名词,在口语中代替many和much,在句中作定语。例如: I read a lot of story-books.

the most famous

最著名的,most 形容词最高级的一种形式,在形容词前加 the most 构成,意为:“最……” 例如The Sahara is the biggest desert in the world.

　 形容词most前面没有the，不表示最高级的含义，只表示"非常"。　It is a most important problem. =It is a very important problem.

more than

超过,多于 ，具体如下：

A. “More than+名词”表示“多于……”、“非但……尤其是”如： 

1)Modern science is more than a large amount of information. 

2)Jason is more than a lecturer; he is a writer, too. 

B. “More than+数词”含“以上”或“不止”之意，如： 

3)?I have known David for more than 20 years.
 

not only……but also

not only……but also? 不但……而且……,是一个表示并列关系的连词,用来连接两个并列关系的句子成分. not only与but also后面所连接的词的词性必须对等： 
例如，Frankin was considered not only an inventor,but also a statesman. （富兰克林不仅被看作发明家，而且被看作政治家 ）

at the age of

在…岁时,例如，He became a doctor at the age of 27.（他27岁时成了一名医生 )