Sentence Correction

Hi,

When to use the below

1) and ......
2),and .....



are the sentences correct?

1)Jobs was unlike Churchill,the PM who was judged to have been a failure before he made a comeback to save his legacy.


2)Jobs was unlike Churchill,the PM who had been a failure before he made a comeback to save his legacy.



3)Jobs was unlike Churchill,the PM who was judged to be a failure before he made a comeback to save his legacy.




4)Many countries ,like China,want to follow the business model

5)Many countries ,such as China ,want to follow the business model.

You will use comma + and when you are separating two independent clauses, which are phrases that can stand as a sentence by themselves. You remove the comma when the compounding predicates, such as:

Tom went to the store and bought some eggs.

Tom is doing the actions before and after the and


As for the other issues:

like and unlike are used to compare nouns.
as is used to compare verbs
such as is used to give examples.