How to use "If and Should" Hello everyone, I have been studying English with the book “English Grammar in Use – Cambridge”. In Unit 32 – Should 2 there is the following explanation: [...] If...Should... You can say “If something should happen...”. For example: If Tom should phone while I’m out, tell him I’ll call him back later. “If Tom should phone” is similar to “It Tom phones”. With should, the speaker feels that the possibility is smaller. Another example: We have no jobs at present. But if the situation should change, we’ll let you know. You can also begin these sentences with should (Should something happens...): Should Tom phone, tell him I’ll call him back later. [...] I have to say I think the explanation a little confuse and I prefer to use the examples without "should", like: It Tom phones while I’m out, tell him I’ll call him back later. We have no jobs at present. But if the situation change, we’ll let you know. If Tom phone, tell him I’ll call him back later. But I’m learning English, so I want to know if it's important to know how to use "IF and SHOULD" together. Is it common? Who speaks English fluently use these two words together? Thanks for the help!