pythonのkeyerror

pythonのKeyErrorについて教えてください。よろしくお願いします。

発生している問題・エラーメッセージ

correct_answer = words_dict[question_word]
KeyError: 'wrong'

該当のソースコード

import re
import random

source = "english.txt"

with  open(source,encoding="utf-8_sig") as f:
    data = f.read()

english_words = re.findall("[a-z]+",data)
ja = re.findall("\s.*\n",data)

meanings = []
for word in ja:
    m = re.sub("\t|\n","",word)
    meanings.append(m)

words_dict = dict(zip(english_words,meanings))


n_tests = 50
n_questions = 50

for test_num in range(n_tests):
    with open("英単語テスト_{:02d}.txt".format(test_num+1),"w")as f:

        f.write("出席番号：\n"
                "名前：\n\n"
                "第{}回 英単語テスト\n\n".format(test_num + 1))

        for question_num in range(n_questions):
            question_word = random.choice(english_words)
            correct_answer = words_dict[question_word]

            meanings_copy = meanings.copy()
            meanings_copy.remove(correct_answer)
            wrong_answers = random.sample(meanings_copy,3)

            answer_options = [correct_answer] + wrong_answers

            random.shuffle(answer_options)

            f.write("問{}.{}\n\n".format(question_num + 1,question_word))

            for i in range(4):
                f.write("{}.{}\n".format(i + 1,answer_options[i]))
            f.write("\n\n")