急！and和逗号用法的问题

76ersgirl

1.   是 I have to point out that the author overstates A's significance and fails to think about other factors.

      还是 I have to point out that the author overstates A's significance ，and fails to think about other factors.

      还是都行？

      另外fail是应该加s吧？

2.   是 There is not a universal answer to the question and whether one choice is to be selected should depend on several other reasons.

      还是 There is not a universal answer to the question ，and whether one choice is to be selected should depend on several other reasons.

      还是都行？

（第一个是从句中的主语干的2件事，第二题是两个独立的句子。）

Euphekira

第一题不能加逗号的，需要加s
第二题需要加逗号，否则就是run-on sentence

76ersgirl

知道了~谢谢！^_^