ば

There are several different ways to express 'if' in Japanese. One of these is through using the conjunction particle ば. ば presents hypothetical situations (possibilities), and pairs with verbs using an う to え sound-change conjugation method on the terminal (last) kana. Let's examine this with a few verbs first.

As we can see with these verbs, the final kana will change to an え sound, from its original う (る to れ, う to え, く to け, す to せ, etc.) before adding ば. It is important to practice these, to not get them mixed up with verbs that use れる, and られる. Unlike with these verbs, the base form of する and くる will not change when using ば.

To conjugate い-Adjectives with ば, the い will be replaced with けれ, one of the standard い-Adjective conjugation forms. After this, just add ば.

For な-Adjectives, and nouns, なら (another standard conjugation form of these words) will be added, before attaching ば.

In the negative form (using ない), both the auxiliary verb ない, and the い-Adjective ない will conjugate in the same way. Simply replace い with けれ, and then add ば.