If the weather is fine she meet her friends at the weekends.

Answer:

If the weather is fine she meet her friends at the weekends.

If the weather is fine she meets her friends at the weekends.

This is a zero conditional sentence. We use it when the weather is generally fine, she usually meets her friends at the weekends.

Это предложение с нулевым условием. Мы используем его, когда погода в целом хорошая, она обычно встречается со своими друзьями по выходным.