The remaining sentences in the average 23 - sentence review offered either mixed or neutral observations. (awfj.org)
So if you even just leave a one sentence review for a favorite author, you are helping make the book more visible to others. (anneduguidcouk.ipage.com)
I try to write 1 - 3 sentences reviews of everything on the Reading / Writing Lists — sometimes longer. (imaginaryplanet.net)