DictationListen to the passage. For questions 21—25, fill in the blanks with th

Dictation
Listen to the passage. For questions 21—25, fill in the blanks with the exact words or phrases you hear.
If you yearn for smooth skin that glows with youth, the chances are that at some point you will have heard the exhortation to drink lots of water in order to flush out those evil toxins and keep your skin healthy.
The exact amount people suggest varies. US-based advice tends to recommend eight glasses a day, while in hotter climates people are advised to drink more to compensate for higher rates of sweating. But regardless of the exact volume of water suggested, the principle behind the advice remains the same—taking extra water on board will keep your skin hydrated. In other words, water acts like a moisturiser, but from the inside out.
This is such a common idea you might be surprised at the lack of evidence to back up. You might expect there to be countless studies where people are separated into two groups, one assigned to sip water all day, the other to drink a normal amount. Then the smoothness of the skin could be assessed a month or so later to establish whether sipping more led to smoother skin.