R：通过标签组合不同长度的频率列表？

我是R的新手，但我真的很喜欢它，并希望不断提高。现在，在寻找了一段时间后，我需要你帮忙

这是给定的情况：

1） 我有句子（句子1和句子2-所有单词都是小写），并创建单词的排序频率列表：

sentence.1 <- "bob buys this car, although his old car is still fine." # saves the sentence into sentence.1
sentence.2 <- "a car can cost you very much per month."

sentence.1.list <- strsplit(sentence.1, "\\W+", perl=T) #(I have these following commands thanks to Stefan Gries) we split the sentence at non-word characters
sentence.2.list <- strsplit(sentence.2, "\\W+", perl=T)

sentence.1.vector <- unlist(sentence.1.list) # then we create a vector of the list
sentence.2.vector <- unlist(sentence.2.list) # vectorizes the list

sentence.1.freq <- table(sentence.1.vector) # and finally create the frequency lists for 
sentence.2.freq <- table(sentence.2.vector)

现在，请问，我如何将这两个频率列表结合起来，我将有以下内容：

 a  although  bob  buys  can  car  cost fine his  is  month much old per still this very you
NA         1    1     1   NA    2    NA    1   1   1     NA   NA   1  NA     1    1   NA  NA
 1        NA   NA    NA    1    1     1   NA  NA  NA      1    1  NA   1    NA   NA    1   1

因此，该“表格”应具有“灵活性”，以便在输入新句子时，如“and”，表格将在“a”和“虽然”之间添加带有“and”标签的列

我只想在新行中添加新句子，并将所有尚未在列表列中的not单词（此处，“and”将位于“you”的右侧），然后再次对列表进行排序。但是，我还没有做到这一点，因为根据现有标签对新句子的单词频率进行排序已经不起作用了（当再次出现例如“car”时，新句子的car频率应该写入新句子的行和列“car”，但当出现例如“you”时这是第一次，它的频率应该写在新句子的行和一个新的列中，标记为“you”）。

这并不是您所描述的，但您的目标对我来说更合理，它是按行组织的，而不是按列组织的（而且R处理以这种方式组织的数据更容易一些）

#将表格转换为数据帧
乔兰，你救了我一天！这就是我所需要的，它看起来很完美。非常感谢。
 a  although  bob  buys  can  car  cost fine his  is  month much old per still this very you
NA         1    1     1   NA    2    NA    1   1   1     NA   NA   1  NA     1    1   NA  NA
 1        NA   NA    NA    1    1     1   NA  NA  NA      1    1  NA   1    NA   NA    1   1

#Convert tables to data frames
a1 <- as.data.frame(sentence.1.freq)
a2 <- as.data.frame(sentence.2.freq)

#There are other options here, see note below
colnames(a1) <- colnames(a2) <- c('word','freq')
#Then merge
merge(a1,a2,by = "word",all = TRUE)
       word freq.x freq.y
1  although      1     NA
2       bob      1     NA
3      buys      1     NA
4       car      2      1
5      fine      1     NA
6       his      1     NA
7        is      1     NA
8       old      1     NA
9     still      1     NA
10     this      1     NA
11        a     NA      1
12      can     NA      1
13     cost     NA      1
14    month     NA      1
15     much     NA      1
16      per     NA      1
17     very     NA      1
18      you     NA      1