条件表現N4
〜ば
if... (general condition)
Structure
V-ば形（え段+ば）；い形容詞（語幹+ければ）；な形容詞（語幹+ならば）
Explanation
Verb ba-form + ば or い-adjective minus い + ければ marks a condition, "if...", often for general or objective relations. E.g., 春になれば、桜が咲く.
Examples
天気がよければ、出かけましょう。
Let's go out if the weather is nice.
安ければ、買います。
If it's cheap, I'll buy it.
Note
ば marks objective, general conditions; the result clause cannot be a strong volitional like a command or request. Often pairs with ほど. 〜ばいい means "it'd be good if...".