1.   The roof always leaks when it rains.

2.   The roof is leaking.

3.   The roof leaks every time it rains.

4.   To add insult to injury the roof leaked.

5.   The roof leaked.

6.   The waterspout became clogged, and then the roof leaked.

7.   But the family simply shrugged and patted the air and went to the far end of the street, and moved into a cottage whose roof did not leak.

8.   A roof leaked, demonstrating the penetrating power of drizzle.

9.   A roof leaked.

10.   But after about four hours, it rained and the flat roof leaked like a colander.