Last week, I made up three sentences for my non-native English speaking friends to comment on. I have written them below.
(1a) This is an interesting, exciting story.
(2a) He is a reliable, dedicated employee.
(3a) The couple has a happy, healthy relationship.
My friends said the sentences sound wrong without the conjunction. So, they revised them to make the sentences below.
(1b) This is an interesting and exciting story.
(2b) He is a reliable and dedicated employee.
(3b) The couple has a happy and healthy relationship.
Are my original sentences wrong without the conjunction? Thank you for your help.