2 части предложения
Main clause – основное
If-clause (condition) – условное
Не только if:
Unless
Providing
Provided
(that)
As long as
In case
On condition (that)
Otherwise
Or else
What if
Supposing
Even if
Only if
If you don’t reserve a ticket, you won’t get a seat.
Unless you reserve a ticket, you won’t get a seat.
Only if you reserve a ticket, you will get a seat.
Reserve a ticket, otherwise you won’t get a seat.
What if he doesn’t reserve tickets, will you still go with him?
Supposing he reserves wrong tickets, will you still go with him?
Will you still go with him even if he reserves wrong tickets.