value = input("Enter string: ")
value = value.strip()
if value[0].isupper() and value[len(value)-1] == '.' or value[len(value)-1] == '?' or value[len(value)-1] == '!':
    print("This string might be a sentence.")
else:
    print("This string is probably not a sentence.")
    if not value[0].isupper():
        print("It does not start with a capital letter.")
    if not (value[len(value)-1] == '.' or value[len(value)-1] == '?' or value[len(value)-1] == '!'):
        print("It does not end with a valid punctuation mark.")

#if not (value[0].isupper() and value[len(value)-1] == '.' or value[len(value)-1] == '?' or value[len(value)-1] == '!'):
print("This will always execute")