ご質問ありがとうございます。
大小は、"Large"/"Small"をそれぞれ使って表現します。
ちなみに普通は、"Medium"/"Regular"のどちらも使えますよ。
Would you like the large rice or small?
あなたは、大盛りライスか、少なめ、どちらが良いですか？
お役に立てれば幸いです。
Would you like a large portion of rice or a small one?
Which size rice portion would you like?
When you say "the large" or "the small" it means the large or the small size serving. Sometimes there is another option, "the medium".
"Portion" is another way to say serving size.
If the customer is familiar with the size options you may ask, "Which size would you like?"
"the large" や "the small" と言うと、これは「ラージサイズ」「スモールサイズ」を指します。もう一つ、"the medium"（ミディアム）という選択肢があることもあります。
"Portion" は一人前の量を指します。
相手がサイズの選択肢を知っているときは、"Which size would you like?"（どのサイズにしますか）と言えます。
We have a small portion and a large portion, which would you like to order?
Would you like the large or small portion of rice?
Between the large and small portion of rice, which would you prefer?
Restaurants sell different sized portions for available meals.
Small, medium, large and extra large are the main popular meal portions.
"I would like to have a small portion of rice, please."
"What size would you like your meal to be?"
レストランでは、色々なサイズの料理があります。
Small（小）, medium（中）, large（大）, extra large（特盛）がよくあるサイズです。
"I would like to have a small portion of rice, please."
（ご飯小をください。）
"What size would you like your meal to be?"
（お料理のサイズはいかがされますか？）
"We have two options, a large portion of rice or a small portion. Which would you like?"
If you worked at a restaurant and you want to ask a customer if they would like a small or large portion of rice, you could say either of the following: "Would you like a small or large rice?" or "We have two options, a large portion of rice or a small portion. Which would you like?". Both ask the question directly.
レストランで働いているのですね。お客さんに「ライスは大盛りにしますか、少な目にしますか」と質問したいと。これは次のように言えます。
"Would you like a small or large rice?"（ライスは少な目がいいですか、大盛りにしますか）
"We have two options, a large portion of rice or a small portion. Which would you like?"（ライスは大盛りと少な目の二つがあります、どちらがいいですか）
どちらも単刀直入な言い方です。
Will you be having a small helping or a big helping of rice with that?
Would like a small serving or a big serving of rice with your meal?
1.Will you be having a small helping or a big helping of
rice with that?
A helping is another word for a portion/serving/bowl or plate.
The phrase "with that" obviously refers to the meal that the
customer or patron has ordered.
2.Would like a small serving or a big serving of rice
with your meal?
As stated earlier, another word commonly used for a
portion/helping/bowl or plate is a serving.
1. Will you be having a small helping or a big helping of rice with that?（ご飯は大盛りにしますかそれとも少な目にしますか）
'helping' は 'portion'（一人前）、'serving'（一人前）、'bowl'（どんぶり一杯）や 'plate'（一皿）と同じ意味です。'with that' は当然、注文した食事を指します。
2.Would you like a small serving or a big serving of rice with your meal?（ご飯は大盛りにしますかそれとも少な目にしますか）
上で述べたとおり、'serving' も「一人分の量、一杯、一皿」という意味でよく使われます。
Which portion of rice would you like to have, large or small?
Would you like a large rice or small?
If you want to ask a customer at a restaurant if they'd prefer the large portion of rice or the small portion ,you can ask the following questions:-
1. Which portion of rice would you like to have, large or small?
If the rice at your restaurant is available in two portion sizes, you can ask the customer which portion he/she would like to have.
2. Would you like a large rice or small?
ご飯を大盛りにするか少な目にするかお客さんに聞きたいなら、次のように言えます。
1. Which portion of rice would you like to have, large or small?（ご飯は大盛りにしますか、それとも少な目ですか）
これは、ご飯のサイズが 'large'（大盛り）と 'small'（少な目）しかない場合に使うことができます。
2. Would you like a large rice or small?（ご飯は大盛りにしますか、それとも少な目ですか）
When talking about large or small rice you are either talking about the grain of rice, as in small grain or large grain or the portion size. In this case, you might say, a small bowl of rice or a large bowl of rice.
"large rice" または "small rice" は二通りの解釈が可能です。一つは「米の粒が大きいまたは小さい」、もう一つは「一人前の量」です。この場合は "a small bowl of rice"（少な目のライス）または "a large bowl of rice"（大盛りのライス）と言えます。
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