要不是 (if it weren't for)

One person away from disaster

• if it were not for要不是yào bú shì … ，… = "if it weren't for … , …" — a counterfactual.
• if it were not for要不是yào bú shìyou你nǐ，I / me我wǒthen / just就jiùto lose the way迷路mí lù(completed / change)了le = "if it weren't for you, I'd have got lost."
• It imagines the opposite of what actually happened.

if it were not for要不是yào bú shì + X，(then / just就jiù) …

• if it were not for要不是yào bú shì supposes X had not been true, then states the result.

if not for要不是yào bù shìyou你nǐ，I我wǒthen就jiùget lost迷路mí lù了le。

• if it were not for要不是yào bú shìyou你nǐ，I / me我wǒthen / just就jiùto lose the way迷路mí lù(completed / change)了le = "if not for you, I'd have got lost."

Recap

Read the full reference: HSK 5 grammar — Sentence patterns.