This page is to help you choose the right part of speech for complain / complaint / complained etc.

        Grammar Notes:

        Word Part of Speech Examples
        to complain infinitive verb I would like to complain about your services.
        complains third person verb He complains all the time.
        complained past tense verb Customers complained about our services last year.

        I complained to the customer service representative 2 weeks ago.

        have complained present perfect verb Recently several customers have complained about this problem.
        complaining continuous verb Customers are complaining about our services.
        adjective We value complaining customers because they help us to improve.
        gerund Complaining makes me feel better.
        complaint noun I have received a complaint about our services.
        (meaning: obedient / co-operative)
        adjective The company is a compliant customer.


        • complain about + problem ( a noun or noun phrase); e.g. 'I would like to complain about your services'.
        • complain to + a person; e.g. 'I complained to the customer service representative'.
        • complained of + a medical problem; e.g. 'He complained of not sleeping well'.
        • complaint of + date the complaint was written; e.g. 'I received your complaint of '.
        • complaint on + date the complaint was received; e.g. 'I received your complaint on '.
        • complained that + clause; e.g. 'He complained that we had not answered his e-mails'.


        Read this situation, then do the following exercise.

        You are an administrator for Exhibitions International, a company which organises business exhibitions and trade fairs around the world. You have received the following letter of complaint about your company's most recent exhibition.