Fetching details from the dictionary...
if ... then; when
and
why don't you ...?
the more (one does something)
時間があれば行きたい。
If I have time, I want to go.
安ければ買うつもりです。
If it is cheap, I plan to buy it.
聞けば分かることだ。
It is something you would understand if you asked.