To look somebody up (or look up somebody) is to locate and visit someone you have not seen for a long time.
Examples of use:
1. Look me up if you are ever in England.
2. I went to Newcastle on business last week and I looked up an old friend.
3. My friends were on holiday in my city, so they looked me up and we all went to a restaurant for a meal.
|present simple||look up and looks up|
|-ing form||looking up|
|past simple||looked up|
|past participle||looked up|
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