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I don’t know - definition and synonyms

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90% of the time, speakers of English use just 7,500 words in speech and writing. These words appear in red, and are graded with stars. One-star words are frequent, two-star words are more frequent, and three-star words are the most frequent.

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  1. 1
    used for saying that you are not certain about something
    I don’t know whether:

    I don’t know whether economic issues were discussed specifically.

  2. 2
    used for saying that you do not completely agree

    ‘It’ll be boring.’ ‘Oh I don’t know. It might be fun.’

    I don’t know that:

    I don’t know that we need to discuss this.

  3. 3
    used when you are giving your opinion and want to find out what someone else thinks

    I don’t know about you, but I’m starving.

  4. 4
    used for criticizing someone
    I don’t know what/how/why etc:

    I don’t know what they were thinking of.

    I don’t know how he could be so cruel.

See also main entry: know


a lifestyle focussing on simple pleasures such as comfort and cosiness in the home, and spending time with friends and family

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a form of location that involves the underwater detonation of a bomb which causes sound waves that are picked up by ships

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