dataset1_sample <- sample(dataset1$twt_txt, 5)
dataset2_sample <- sample(dataset2$twt_txt, 5)
dataset3_sample <- sample(dataset3$twt_txt, 5)

dataset1_sample
[1] These
[2] Are
[3] My
[4] Test
[5] Words
9741 Levels: ''A lot of text'' That I do not understand why it is all in here.

class(dataset1_sample) = factor

listoflists <- list(list(dataset1_sample),list(dataset2_sample))

test <- cbind(dataset1_sample, dataset2_sample)

df <- read.csv("file.csv", stringsAsFactors=TRUE)