A prefix is a series of letters, or a word, that is added to the  beginning of a word and changes the meaning. For example, in the  word midnight, mid is the prefix.
The more vigorous an activity, however, the more calories youâll burn. Changes in body weight are related to both the duration and intensity of play. Playing singles tennis at average intensity expends 300-600 kcal/h, while high intensity tennis training expends 450-900 kcal/h. Diabetes. The incidence of diabetes worldwide of persons aged 20 or above in 1995 was 4% (approx. 135 million), a figure that will increase to approx. 5.4% (300 million people) by 2025.
Wimbledon crowd sees the longest tennis match ever â and it's still going. Apparently not, it seemed. Last night, France's Nicolas Mahut and John Isner from the US, two of the lesser known names on the men's singles circuit, remained deadlocked on two sets each and both with 59 games in the longest fifth set ever, of the longest tennis match ever.