word = {}

def train():
    with (open("vocab.txt", "r+")) as vocab:
        for line in vocab:
            word[line] = vocab.readline()

    try:
        while True:
            if input(f"what is the translation of '{word[0]}'? ") in word[1]:
                print("correct!")
                break
            else:
                print("incorrect, try again")

    except KeyError:
        print("no such word in the library!")
        print()

def save_vocab():
    ger = input("enter a german word: ")
    en = input("enter an english translation: ")

    with (open("vocab.txt", "w")) as vocab:
        vocab.write(f"{ger}, {en}")



while True:
    print("1. Add a new word")
    print("2. Train")
    print("3. Quit")

    user_inp = input()
    if user_inp == "1":
        save_vocab()
    if user_inp == "2":
        train()
    if user_inp == "3":
        break