take up意思：拿起；开始从事；占据(时间,地方)
take in意思：接受；理解；拘留；欺骗；让…进入；改短
双语列句
take in：
He persuaded Jo to take him in
他说服乔把他收留了下来。
Lesley explains possible treatments but you can tell she's not taking it in
莱斯利解释了各种可行的疗法，不过，你可以看出来，她并没有领会。
They will certainly need to take in plenty of liquid.
它们当然需要吸收大量液体。
take up：
He did not particularly want to take up a competitive sport
他并不特别想从事竞技体育运动。
Mr de Garis's MP, Max Madden, took up the case
德加里斯先生的下议员马克斯·马登开始着手处理这个问题。
Angela used to be a model and has decided to take it up again.
安杰拉以前当过模特，现已决定重操旧业了。