First conditional is used to talk about a possible future condition and its result.
| If (condition) | + present simple | + will (result) | + verb |
|---|---|---|---|
| If | it snows | we'll | go skiing. |
| it doesn't snow | we won't |
Second conditional is used to talk about an improbable or impossible condition and its result.
| If (improbable condition) | + past simple | + would (result) | + verb |
|---|---|---|---|
| If | I lived in Rome | I'd | learn Italian quickly. |
| I didn't live in London |