a lot of 是既可以修饰可数名词,也可以修饰不可数名词。many只能修饰可数名词的复数。而且a lot of 可以修饰比较级,而many不可以。
例句a lot of
1、I have lost a lot of weight.
我体重减了不少。
many
1、How many years have you been here?
你在这里有多少年了?
水利万物而不争,
而万物莫能与之争。