Answer:
<em>In an interview last month on the Yoga Up! Website, Don Roth, a yogi with 30 years' experience wrote how regular yoga "helps your tendons, muscles and ligaments achieve full movement, whilst also improving your core strength." He also added that performing yoga regularly, no matter what sport you play, can improve your performance and reduce the chance of injuries.
</em>
Explanation:
Commas, in general, are used to provide a pause, a shortstop, or to separate between items in a list. They are also used to separate clauses or to specify a proper noun etc. The given passage has 4 errors in the usage of the comma. The improved or correct passage will be-
<em>In an interview last month on the Yoga Up! Website, Don Roth, a yogi with 30 years' experience wrote how regular yoga "helps your tendons, muscles and ligaments achieve full movement, whilst also improving your core strength." He also added that performing yoga regularly, no matter what sport you play, can improve your performance and reduce the chance of injuries.
</em>
The corrections are as follows-
Remove comma after "month",
add comma after "Roth",
remove comma after "yoga",
add comma after "play".
