The usage of 有 in comparisons The verb 有 can be used to form a sentence in a way of comparisons of equality as follows. (as ~ as)

今天有昨天热。Today is as hot as yesterday.
他没有你细心。He is not as careful as you.

From looking at them, it seems to me that Mandarin uses a phrase (noun+adjective) as one word, for example in the above two sentences:

昨天-热 (hot as yesterday)
你-细心(careful as you)

Am I getting it correct? If yes, can I do the make-up-new-word thing when I speak English in Mandarin too as long as it fits well?
or this is not a good catch at all?
Thank you all in advance.
When use 有 in comparison: 

In positive way you can use 今天和昨天一样热(Today is as hot as yesterday) or 今天有昨天那么热 instead of 今天有昨天热.Because it's more normal expression.

In negative way you can use 他没(有)你(那么)细心 which will omit character 有 or 今天没(有)昨天(那么)热.

It's better to add 那么 in comparison to emphasize comparison.