Add punctuation: But no young puffins were seen on their way to the sea and as no one was seen towards the end of the month it has to be concluded that the puffins again had a very unsuccessful breeding season though it in the beginning seemed very promising
A: But no young puffins were seen on their way to the sea and as no one was seen towards the end of the month, it has to be concluded, that the puffins again had a very unsuccessful breeding season, though it in the beginning seemed very promising.

Add punctuation: The sin against the Holy Spirit cannot be forgiven
A: The sin against the Holy Spirit cannot be forgiven,.

Add punctuation: In addition resistance regulates automatically according to power of stroke the stronger you pull the stronger gets the resistance
A:
In addition, resistance regulates automatically according to power of stroke: the stronger you pull, the stronger gets the resistance.