Translation

• hard to say
• can't guarantee
• difficult to protect
• difficult to preserve

Synonyms

• 保不定, 没准, 难说

Examples

• 白色的地毡很难保持乾净。
  White carpets are very hard to keep clean.
• 在结冰的街道上我们很难保持平衡。
  It is hard to keep our balance on icy streets.