1. ApplePie is very attractive.2. She is very smart.
I am going to use the above two sentences to show you how to write a correct one / ones. 
Grammatically Correct Versions
- ApplePie is very attractive, and she is very smart. (Compound Sentence)
- ApplePie is very attractive; she is very smart. (Compound Sentence)
- ApplePie is very attractive; moreover, she is very smart. (Compound Sentence)
- ApplePie is very attractive and smart.
- ApplePie is very attractive. Moreover, she is very smart.
Grammatically Incorrect Versions
- ApplePie is very attractive she is very smart. (Run-On Sentence)
- ApplePie is very attractive, she is very smart.(Comma Splice)
- ApplePie is very attractive and she is very smart.(You need a comma when you use a coordinating conjunction to make a compound sentence)
- ApplePie is very attractive, moreover, she is very smart.(You need a semicolon before a conjunctive adverb not a comma when you make a compound sentence)
- ApplePie is very attractive, and smart.(No comma)
* Having good grammar not only enhances your linguistic comprehension, but it also enhances your credentials and authority in academic writings.