What sentences begin with if?

1. If there is no sowing in spring, there will be no harvest in autumn.

Give up pebbles, there is no road.

3. If one wish can come true, I hope there is no earthquake in Wenchuan; If there is a sun that can light up the darkness, I will send it to the hearts of children with my real name.

If it is sunny today, I will plant sunflower seeds in the sun!