How can I make a list of three sentences to a string? - string

Question

I have a target word and the left and right context that I have to join together. I am using pandas and I try to join the sentences, and the target word, together into a list, which I can then turn into a string so that it would work with my vectorizer. Basically I am just trying to turn a list of three sentences to a string.
This is the error that I get:
AttributeError Traceback (most recent call last)
<ipython-input-195-ae09731d3572> in <module>()
3
4 vectorizer=CountVectorizer(max_features=100000,binary=True,ngram_range=(1,2))
----> 5 feature_matrix=vectorizer.fit_transform(trainTexts)
6 print("shape=",feature_matrix.shape)
3 frames
/usr/local/lib/python3.6/dist-packages/sklearn/feature_extraction/text.py in _preprocess(doc, accent_function, lower)
66 """
67 if lower:
---> 68 doc = doc.lower()
69 if accent_function is not None:
70 doc = accent_function(doc)
AttributeError: 'list' object has no attribute 'lower'
I have tried using .joinand .split but they are not working for me so I am doing something wrong.
import sys
import csv
import random
csv.field_size_limit(sys.maxsize)
trainLabels = []
trainTexts = []
with open ("myTsvFile.tsv") as train:
trainData = [row for row in csv.reader(train, delimiter='\t')]
random.shuffle(trainData)
for example in trainData:
trainLabels.append(example[1])
trainTexts.append(example[3:6])
The indexes example[3:6] means that the 3 is left context 4 is target word and 5 right context.
print('Text:', trainTexts[3])
print('Label:', trainLabels[1])
edited the few printed lines from the code:
['Visa electron käy aika monessa paikassa luottokortista . Mukaanlukien ', 'Paypal', ' , mikä avaa taas lisää ovia .']
['Nyt pistän pääni pölkyllä : ', 'WinForms', ' on ihan ok .']