書ける・
The potential form changes a controllable verb to mean that someone can perform the action, either through personal ability or because circumstances make it possible.
Ability and circumstances
Use the potential form for a learned skill or personal ability, and also when a place, schedule, rule, or other circumstance makes an action available. The person does not always have to be stated when the context makes them clear.
Choosing the particle
The thing that someone can speak, read, eat, or otherwise handle commonly takes が, as in 日本語が話せる. However, do not mechanically replace every を with が. In particular, a route or path still takes を.
工事中ですが、歩行者はこの道を通れます。
Construction is underway, but pedestrians can use this road.
Analyzeこの道を marks the route traveled.
In conversation
The first speaker uses a common shortened conversational form; the reply uses the standard form.
Two important distinctions
見られる and 聞ける describe an intentional opportunity or ability to look or listen. By contrast, 見える and 聞こえる describe something naturally being visible or audible. Also, a standard Group 2 potential form has the same shape as the passive form, so context and the roles marked by particles must identify the meaning.
私は知らない人にじっと見られた。
A stranger stared at me.
AnalyzeThis is passive, not potential: the speaker receives the action, and the person doing the looking is marked by に.
More examples
明日は八時までに来られますか。
Can you come by eight tomorrow?
Analyze昨日は忙しくて、会議に来られませんでした。
I was busy yesterday and couldn't come to the meeting.
Analyzeこのアプリなら、スマートフォンから予約できます。
With this app, you can make a reservation from your smartphone.
Analyze今日は時間があるので、最後まで聞けます。
I have time today, so I can listen until the end.
Analyzeこの箱は重すぎて、一人では運べません。
This box is too heavy for one person to carry.
Analyzeこの配信なら、海外からでも試合を見られます。
With this stream, you can watch the match even from overseas.
Analyze一人で着物が着られますか。
Can you put on a kimono by yourself?
Analyze無事に会場まで来られて、安心しました。
I'm relieved that I was able to make it to the venue safely.
Analyze