silver ravine
i just read in my book, "the duplicated formula of a disyllabic verb is ABAB. As for a monosyllabic verb, 一 or 了 is placed between the verbs to be repeated" （i have doubt in duplication of monosyllabic verbs)
example 1 is: 这本小说很有意思，你可以看看。
now please explain, why it isnt 看一看? is it bcuz it has a disyllabic helping verb "可以"??
and 2ed example is: 则篇课文请你念一念。
example 1 and 2, both have monosyllabic verbs, but only 2ed example is following the rule
median frigate
看一看 is fine here
and for the 2nd example, 念念 is perfectly ok too
i cant think of an example off the top of my head in which X一X is different from XX
random drift
“看看”=“看一看”，“念念”=“念一念”，native speakers do not have the concept of disyllabic verb and monosyllabic verb in Chinese. I guess textbook written in this way is to enable second language learners to standardize the use of Chinese (or to limit multiple similar expressions to one to avoid confusions). The two examples you gave are actually both correct.