youdao

Biofilm communities can harbor bacteria longer and are very difficult to clean.

生物膜群落容纳细菌的时间更长且很难清洗。

youdao

Oh, I see, Carpet can be difficult to clean.

我明白，地毯是很难清洗的。

youdao

Opponents fear a spill would be a disaster, being difficult to clean up in icy seas.

CNN: Why we should look to the Arctic

Garrison Keillor was not quite right when he said that only Americans pulled down old houses because they were too difficult to clean.

ECONOMIST: China��s Communist modernisers are wrecking the capital

Banking messes are horribly difficult to clean up unless the bankers, businessmen and government officials responsible face penalties, especially where, as in Japan, they have committed crimes as well as made blunders.

ECONOMIST: Japanese banking