老师
DRUPAL 老是有人来注册，多是机器注册的

原来的是 （如下过于简单，请问如何自己设计公式呢）
Math question: *
3 + 9 =
Solve this simple math problem and enter the result. E.g. for 1+3, enter 4.

Math question: *
3 + 0 =
Solve this simple math problem and enter the result. E.g. for 1+3, enter 4.

Math question: *
5 + 4 =
Solve this simple math problem and enter the result. E.g. for 1+3, enter 4.

Math question: *
10 + 6 =
Solve this simple math problem and enter the result. E.g. for 1+3, enter 4.

Math question: *
2 + 5 =
Solve this simple math problem and enter the result. E.g. for 1+3, enter 4.

Math question: *
8 + 7 =