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" 4. The Japanese inability to pronounce various vowel sounds found in the English language. The Japanese language contains only 5 basic vowel sounds: "a" as in "ah", "i" as in "eee", "u" pronounced like "ooo", "e" pronounced like "eh", and "o" pronounced like "oh". Such confusion in vowel sounds can lead to examples like "fack you!" in place of "f*ck you", etc.

Grammatical mistakes vary but there are a few common errors that English teachers in Japan see on a daily basis:
1. Using a noun as a verb with "Let's" as in: "Let's beer" or "Let's Kiosk"
2. Redundant wording such as: "Let's play with me!"
3. Dispense with connecting words. Example: "I feel Coke"