ENGLISH
REFERENCE

unable to do sth

fixed phr..
B1 Intermediate Oxford

fixed phr.. you use this to say that you cannot do something because you do not have the skill, time, or power.

fixed phr.. a predicative adjective phrase functioning as the negative counterpart to 'able'; it expresses a lack of capacity, opportunity, or permission to perform an action.


SIMPLE

I am unable to attend the meeting tomorrow.

CONTEXTUAL

Due to the heavy snow, the trains were unable to run on time this morning.

COMPLEX

The witness was unable to provide a detailed description of the suspect because the streetlights were malfunctioning at the time of the incident.

Usage

always followed by a 'to' infinitive and usually follows a form of the verb 'to be'.

Teaching tip

remind students that 'unable' is more formal than 'can't' and is frequently used in professional emails or official announcements.

Pitfall

I am unable doing it.I am unable to do it.the phrase requires a 'to' infinitive, not a gerund (-ing form).

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