Learn Spanish (Latin America): Lo que pasa es que la grúa no llega. - The thing is, the tow truck isn't arriving.

It acts as a conversational tool to introduce an explanation, a justification, or an excuse. While you could just say la grúa no llega, adding lo que pasa es que translates perfectly to 'The thing is...' or 'What's happening is that...' to soften the bad news or explain a delay.

Literally translated, doesn't lo que pasa es que mean 'what passes is that'?

Yes, almost! The verb pasar frequently means 'to happen' in Spanish. So, word-for-word, it is 'what happens is that' (using lo que for 'what' or 'that which'). In natural English, we usually just say 'the thing is.'

Why is llega in the indicative mood rather than the subjunctive?

Even though it is a long phrase ending in que, lo que pasa es que introduces a known fact or reality (the truck isn't arriving). Since it declares a fact rather than expressing doubt, desire, or emotion, it triggers the indicative mood (llega) instead of the subjunctive (llegue).

Why does the English translation say 'isn't arriving' when llega is the simple present tense?

In Spanish, the simple present tense (llega) is often used to talk about actions happening right now, where English prefers the present continuous ('is arriving'). Saying no está llegando is possible, but no llega is the more natural and common way to express 'it isn't arriving' or 'it hasn't shown up yet.'