Potential Complement: “Verb + 得 / 不 + 了”
In Chinese, “得了” (de liǎo) or “不了” (bù liǎo) follow the verb and say whether the action can or cannot be carried out.
The pattern can also go inside a 离合词 (separable verb).
How it is translated
… be able to do it
… be unable to do it
… it is / is not possible
Basic structure
Verb + 得了
… can do it / it is possible
Verb + 不了
… cannot do it / it is not possible
手机没有信号，上不了网，买不了地铁票了
上 + 不了 + 网
go + be unable to + online
be unable to get online
买 + 不了 + 地铁票
buy + be unable to + subway ticket
be unable to buy a subway ticket
手机没有信号 — the phone has no signal
上不了网 — cannot get online
买不了地铁票 — cannot buy a subway ticket
她刚才给我发信息，说她今天来不了了
来 + 不了
come + be unable to
刚才 — just now
给我发信息 — send me a message
今天来不了 — cannot come today
Here “来不了” means “cannot come”.
明天的足球比赛，你们班男生参加得了吗？
参加 + 得了 + 吗？
take part + be able to + ?
明天的足球比赛 — tomorrow’s football match
你们班男生 — the boys in your class
参加得了吗 — will they be able to take part?
Here “得了” asks whether the action is possible.
With separable verbs
“得了 / 不了” can also be inserted inside a separable verb.
Verb part + 得了 / 不了 + noun part
This too says whether the action can be carried out.
Rule in brief
Verb + 得了
… be able to do it
Verb + 不了
… be unable to do it
上不了网
买不了地铁票
来不了
参加得了吗？