QUESTION: Fix punctuation: I guess most of the Greeks you see work for the tourist business
ANS: I guess most of the Greeks, you see, work for the tourist business.

QUESTION: Fix punctuation: It also provides tool to fix iOS device if you encounter sync problems iPhone Care Pro for Mac is a great iOS ads blocker which easily blocks or removes ads and banners in apps on iPhone iPad and iPod Touch It creates a totally adfree environment for your iOS devices
ANS: It also provides tool to fix iOS device if you encounter sync problems. iPhone Care Pro for Mac is a great iOS ads blocker which easily blocks or removes ads and banners in apps on iPhone, iPad and iPod Touch. It creates a totally ad-free environment for your iOS devices.

QUESTION: Fix punctuation: Manufacturing hybrid high impulse systems opens up a new world of flexibility but it is also of paramount importance that you are aware of the requirement specifications for the ventilation system
ANS: Manufacturing hybrid high impulse systems opens up a new world of flexibility, but it is also of paramount importance that you are aware of the requirement specifications for the ventilation system.

QUESTION: Fix punctuation: But in the later 1950s the US Senate Labor Committee under the chairmanship of John McClellan which had been investigating corruption in American labor unions began to investigate Dave Beck and the Teamsters Union Robert Kennedy was the Committee counsel responsible for this investigation
ANS:
But in the later 1950's the U.S. Senate Labor Committee under the chairmanship of John McClellan which had been investigating corruption in American labor unions began to investigate Dave Beck and the Teamsters Union. Robert Kennedy was the Committee counsel responsible for this investigation.