QUESTION: Fix punctuation: You can then try again
ANS: You can then try again.

QUESTION: Fix punctuation: Checking the cells for specific genes can now be done on the fetal cell cultures
ANS: Checking the cells for specific genes can now be done on the fetal cell cultures.

QUESTION: Fix punctuation: I want to thank Niklas for many years of hard work and high commitment and wish him all the best in his future career says Peter Dahlgren CEO of Nordnet
ANS: I want to thank Niklas for many years of hard work and high commitment and wish him all the best in his future career" says Peter Dahlgren, CEO of Nordnet.

QUESTION: Fix punctuation: Both meet eye to eye as authors with the user claiming and being granted expert status which was previously the sole province of the architect
ANS:
Both meet eye to eye as authors, with the user claiming and being granted expert status, which was previously the sole province of the architect.