可能形
Potential form — "can do something" (食べられる、書ける)machine translation
FormationGroup 1: う row → え row + る；group 2: drop る + られる；する → できる、来る → 来られる
The potential form expresses "can do something": 書ける (can write), 食べられる (can eat). Compared with the pattern 〜ことができる, also learned at N4, the potential form is shorter and used far more often in conversation.
How to conjugate: group 1 changes the final sound from the う row to the え row and adds る: 書く → 書ける, 読む → 読める, 買う → 買える. Group 2 drops る and adds られる: 食べる → 食べられる, 見る → 見られる. Group 3: する → できる, 来る → 来られる (こられる). Once converted to the potential form, a verb always conjugates on as a group 2 verb.
With the potential form, the object's particle usually changes from を to が: 漢字を読む → 漢字が読める. In casual speech, Japanese speakers often drop the ら in group 2 (食べれる, 見れる) — you need to understand this when you hear it, but use the full forms in writing and on the JLPT.
Note: the potential form is only for intentional actions. For "naturally being able to see or hear", Japanese has the dedicated verb pair 見える・聞こえる — you'll learn them in the very next lesson.
Examples
私は漢字が少し読めます。
I can read kanji a little.
妹は納豆が食べられません。
My little sister can't eat natto.
明日のパーティーに来られますか。
Can you come to tomorrow's party?