QUESTION: Fix punctuation: Pittsburgh is a major port city on the Ohio River which is the financial and commercial center of America founded in 1761
ANS: Pittsburgh is a major port city on the Ohio River, which is the financial and commercial center of America founded in 1761.

QUESTION: Fix punctuation: When skin cell replacement decreases skin becomes thinner and more fragile
ANS: When skin cell replacement decreases, skin becomes thinner and more fragile.

QUESTION: Fix punctuation: It is a pleasure to see the embroidered image slowly appear as you sew
ANS: It is a pleasure to see the embroidered image slowly appear as you sew.

QUESTION: Fix punctuation: On Friday we can expect mostly sunny weather Morning temperatures will be around 19 C During the day they will reach a maximum of 36 C Low temperatures at night will be around 22C Southeasterly winds are weak
ANS:
On Friday we can expect mostly sunny weather. Morning temperatures will be around 19 C. During the day they will reach a maximum of 36 C. Low temperatures at night will be around 22C. Southeasterly winds are weak.