我们不得不重新开始。

We had to start ___all ___over ___again.

挫折之后，他不得不重新开始他的项目。

After the setback, he had to begin his project ___all ___over ___again.

如果你忘了基础，可能就需要重新学习。

If you forget the basics, you might need to learn them ___all ___over ___again.