It is asking you to identify the present perfect verb form.
Let's practise
Tick the correct present perfect verb form below to complete the sentence.
Mark and Melissa to know each other since they started school.
know
knew
have known
knows
- Read the question carefully and read it again. What is it asking you to do?
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- Look for clues in the sentence to show when the actions are happening.
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The action begins in the past and continues to the present.
- Check the possible verb forms that may fit.
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Have known is the only option that would fit. Tick have known.
- Check your answer.
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have known