He made a huge blot on his copybook.

他在练习册上弄了一个大的污渍。

youdao

There was still time in the final few minutes for Messi to slightly blot his copybook by allowing Enyeama to save from six yards when he should have scored but it is harsh to take away from what was a superb display from the forward and an encouraging victory for Maradona's men.

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The only blot on his copybook was an arrest for using heroin in the mid 60s, which forced him to kick the habit.

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