"亲爱的外教老师" 用英语可以说作 "Dear foreign teacher"。
"Dear" 是英语中表示"亲爱的"的词汇，而 "foreign" 是"外国的"的意思。
例句：
Dear foreign teacher, I want to thank you for your patience and help. (亲爱的外教老师，我想感谢你的耐心和帮助。)
Dear foreign teacher, please correct my pronunciation. (亲爱的外教老师，请纠正我的发音。)