an extra serving of rice; an extra portion of rice; extra rice
「ごはん増量で」は英語ならこのようです。
Can I have an extra serving of rice?
Can I get an extra portion of rice?
Serving と portionというのは、だいたい普段の一人分の量です。なので、extra serving か extra portion は普段の量より、増量した分になります。
「Extra rice」も、「ご飯多めで」のような意味です。もし、上記の言い方が少し長くて覚えにくかったら、このように言えば良いです。
Can I get extra rice?
Can I have extra rice?
ご参考までに！
If you have already been served with rice or vegetables and you feel that it is not as much as you would like to eat, you may ask for more rice or vegetables, whichever it is. This rice can also be termed 'extra rice' because it is increasing the quantity of the rice that you already have. The same applies to vegetables.
So, you may say to the waiter:
May I have more rice please?
or
Please serve me with extra vegetables.
or
Will you please bring me extra rice?
すでにご飯や野菜が運ばれてきているのにそれだけでは足りないと感じた時はご飯や野菜のお代わりをもっとお願いするかもしれません。追加でお願いしたご飯を'extra rice' （追加のご飯）といいます。
なぜかというと元のご飯を増量してもらったことになるからです。野菜の場合も同じことが言えます。
よって、ウェイターに以下のように言うことができます。
May I have more rice please?
ご飯をもっといただけますか？
Please serve me with extra vegetables.
野菜の増量をお願いします。
Will you please bring me extra rice?
追加のご飯をいただけますか？
Can I have an extra portion of rice/vegetables on the side.
Can you please add an extra portion of rice/vegetables to my plate.
1. This is asking for a extra serving of rice/veg in a side plate as a side order.
2. This is asking to add a extra serving of rice.veg to your main meal in the same plate as.
Both sentences is appropriate to use depending on how you want it served, in a separate plate or in the same plate with your food.
1. This is asking for a extra serving of rice/veg in a side plate as a side order.
2. This is asking to add a extra serving of rice.veg to your main meal in the same plate as.
どちらの文章でも、あなたがどのようにしたいのか、欲しいか説明することができます。別のプレートまたはあなたの食べ物と同じプレートになど。
Could I please have some extra rice?
Could I please have some more rice?
Could I please have a double serving of vegetables?
Could I please have an extra portion of vegetables?
Could I please have another serving of vegetables?
【例文】
Could I please have some extra rice?
（ご飯をもう少しもらえますか？）
Could I please have some more rice?
（ご飯をもう少しもらえますか？）
Could I please have a double serving of vegetables?
（野菜を2倍もらえますか？）
Could I please have an extra portion of vegetables?
（野菜を余分にもらえますか？）
Could I please have another serving of vegetables?
（野菜のお代わりをもらえますか？）
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