Based on general consensus, here are five languages often considered challenging:

5. Russian Cyrillic alphabet: While similar to some Latin letters, it requires adaptation.

4. Korean Unique alphabet: Hangul is relatively easy to learn, but the language itself presents challenges.

3. Japanese Multiple writing systems: Kanji, Hiragana, and Katakana.

2. Arabic Complex script: Right-to-left writing system and unique characters.

1. Mandarin Chinese Tonal language: The meaning of words can change based on tone, making it difficult for native English speakers.

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