Witaj

keep up:

[1] keep sth up - continue doing sth
[2] keep up the good work - continue to work hard
[3] keep up with - to go as quickly as someone else
[4] keep up with - to manage or do as much as other people
[5] keep up - to continue to read and learn about a particular subject, so that you always know about the most recent facts, products etc
[6] keep sth up - to make something continue at its present level or amount, instead of letting it decrease
[7] keep sth up - to continue to practise a skill so that you do not lose it
[8] keep sb up [informal] - to prevent someone from going to bed
[9] keep your spirits/strength/morale etc up - to stay happy, strong, confident etc by making an effort
[10] keep up appearances - to pretend that everything in your life is normal and happy even though you are in trouble, especially financial trouble
[11] keep up with sb - to write to, telephone, or meet a friend regularly, so that you do not forget each other

PS. Dotrzymywać komuś kroku to 'keep up with'.

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