QUESTION: Fix punctuation: One of the possible underlying causes your doctor will be looking for is thyroid disease particularly if your dog is older
ANS: One of the possible underlying causes your doctor will be looking for is thyroid disease, particularly if your dog is older.

QUESTION: Fix punctuation: In principle a negociant buys wines from producers
ANS: In principle, a negociant buys wines from producers.

QUESTION: Fix punctuation: Cut protection fibre level 3 in the knit ie all round
ANS: Cut protection fibre level 3 in the knit, i.e. all round.

QUESTION: Fix punctuation: No weekly or monthly limits download as often as you like
ANS:
No weekly or monthly limits, download as often as you like