Question about the main clause of conditionals

I know the four types of conditionals. In the if clause, I know that “if” could be replaced by “when” and “should”. On the other hand, I do not know if this would be possible with the main clause. Can we replace the word “would” with other words, like “should or “could”?

Answer

It is possible. Here are a few examples:

1. If someone calls, you should tell them I'm out.


2. If you told me what you need, I could possibly help you.

Please note that "would", "should" and "could" bear different meanings. They are not interchangeable.