on diet 意思是"節食; 減肥"?
on a diet 意思是"遵守飲食特別規定的"
這兩者的意思不壹樣的。
相似短語：
1、go on diets v. 節食
2、I'm on a diet 我正在減肥；我正在節食。
3、to go on a diet 按規定飲食進食。
4、on a diet 按規定進食,進規定的飲食。
例句
1、Let him sequester himself,from the company of his countrymen,and diet in such places,where there is good company of the nation where he travel.
他得使自己不與本國同胞交往，而且應在可結交當地朋友的地方用餐。
2、"Its diet includes fishes, sea turtles, birds, sea lions, small whales, carcasses, and ships' garbage."
食物包括魚類、海龜、海鳥、海獅、海船上所棄雜物等。
3、"Causes: Poor diet, sluggish metabolism, stress, a hormonal imbalance, and sometimes infection."
問題起因:飲食不良,新陳代謝緩慢,壓力,荷爾蒙分泌失調,或許還有感染。
4、but, catching him thus alone, and in his own den, the lion made an easy prey of them, and grew fat upon his diet哪知道這頭獅子就這樣待在自己的洞穴裏，輕而易舉地把探望者壹個個捉住吃掉，把自己養得胖胖的。
5、Action springs not from thought, but from a readiness for responsibility. --Dietrich Bonhoeffer, German theologian.
行動並不來自思想,而是來自願意承擔責任。德國神學家邦赫費爾。