GRAMMAR NOTES
Conditional Sentences
● Level B1–B2 ● Intermediate ●
Conditional sentences express that one situation depends on another. English has four main types, each
used in different contexts. This guide covers their structure, use, and common mistakes.
■ Quick Overview
Type If-clause Main clause Use
Zero Simple Present Simple Present Facts & general truths
First Simple Present will + base verb Real future situations
Second Simple Past would + base verb Hypothetical / unlikely
Third Past Perfect would have + PP Unreal past situations
1 ■ Zero Conditional — Facts & Habits
Use the zero conditional to talk about facts that are always true, scientific truths, and habits. Both clauses
use the Simple Present.
If + Simple Present , Simple Present
Examples
■ If you heat water to 100°C, it boils. ➤ Si calentás agua a 100°C, hierve.
■ If it rains, the streets get wet. ➤ Si llueve, las calles se mojan.
■ Tip: You can replace "if" with "when" in zero conditionals without changing the meaning: "When you heat
water to 100°C, it boils."
2 ■ First Conditional — Real Future
Use the first conditional for real or possible situations in the future. The if-clause uses the Simple
Present; the main clause uses will + base verb.
Conditional Sentences
● Level B1–B2 ● Intermediate ●
Conditional sentences express that one situation depends on another. English has four main types, each
used in different contexts. This guide covers their structure, use, and common mistakes.
■ Quick Overview
Type If-clause Main clause Use
Zero Simple Present Simple Present Facts & general truths
First Simple Present will + base verb Real future situations
Second Simple Past would + base verb Hypothetical / unlikely
Third Past Perfect would have + PP Unreal past situations
1 ■ Zero Conditional — Facts & Habits
Use the zero conditional to talk about facts that are always true, scientific truths, and habits. Both clauses
use the Simple Present.
If + Simple Present , Simple Present
Examples
■ If you heat water to 100°C, it boils. ➤ Si calentás agua a 100°C, hierve.
■ If it rains, the streets get wet. ➤ Si llueve, las calles se mojan.
■ Tip: You can replace "if" with "when" in zero conditionals without changing the meaning: "When you heat
water to 100°C, it boils."
2 ■ First Conditional — Real Future
Use the first conditional for real or possible situations in the future. The if-clause uses the Simple
Present; the main clause uses will + base verb.
