Fill in the Blanks I can / I can'tOnline version Complete the sentences with can or can't. by Modern English 1 can can't can can't can 1 . I can't come now , but I come tomorrow . 2 . I haven't got a computer , so I surf the web . 3 . She's a really good runner - she run a marathon in around 3 hours . 4 . My cat can't swim but it climb trees . 5 . My little sister's three years old . She can walk but she read .