Japanese speakers
Mistake: Pronouncing it as "KYAN YU" with a full [ju:] vowel and clear syllable break.
Why: Katakana English preserves each word and full vowel qualities.
Fix: The n of "can" links directly to the y of "you", and "you" reduces to schwa (or [jə]): [kənˈjə] or [ˈkænˈjə] with emphasis. In fast speech: [ˈkænjə].
Korean speakers
Mistake: Producing full [æ] for "can" and clear [ju:] for "you".
Why: Korean prosody favors clear articulation.
Fix: "Can" reduces to [kən] in unstressed positions (which is the default in questions). "You" reduces to [jə]: [kənˈjə]. Full [kæn ju:] sounds oddly emphatic.
Spanish speakers
Mistake: Producing Spanish [j] with friction, blocking natural linking.
Why: Spanish [j] is a strong onset.
Fix: English [j] is light and glides smoothly from the preceding [n]: [kənˈjə]. Note: "can" is a common example of vowel reduction — [ə] instead of [æ] in unstressed positions.