I would like to order the salad but can I get it in a larger container?
Does the salad come in large sizes?
Can I order a larger salad?
Can the cook make me a large salad even if it's not on the menue?
Can I get a large salad even though I don't see one on the menu?
I would like to order the salad but can I get it in a larger container?
Does the salad come in large sizes?
Can I order a larger salad?
Can I customize the salad? I would like it to be bigger.
Can I please get a larger salad than what is on the menu?
How big is the salad? Can I get a larger one?
I would like an extra large salad please.
Can the cook make me an extra large salad?
Can the cook make me a large salad even if it's not on the menue?（メニューになくても、サラダは大盛りにできますか）
Can I get a large salad even though I don't see one on the menu?（メニューには確認できないのですが、サラダは大盛りにできますか）
I would like to order the salad but can I get it in a larger container?（サラダを注文したいのですが、量を増やすことはできますか）
Does the salad come in large sizes?（サラダは大盛りにできますか）
Can I order a larger salad?（サラダは大盛りにできますか）
Can I customize the salad? I would like it to be bigger.（サラダをカスタマイズできますか。大盛りにしてもらいたいです）
Can I please get a larger salad than what is on the menu?（サラダは大盛りにできますか）
How big is the salad? Can I get a larger one?（サラダはどれくらいのサイズですか。大盛りにできますか）
I would like an extra large salad please.（サラダを特盛りでお願いします）
Can the cook make me an extra large salad?（サラダは特盛りにできますか）
"Could" is the polite way to make a request, especially if you don't know the person. A "portion" is the same as serving size. I hope that this helps. :)
When you want to ask a waiter whether they can make a salad a larger portion; then you may ask in the following ways:
-Can you make a larger portion of this salad?
-Can you make the salad a large potion?
サラダを大盛りにできるかウェイターに確認するなら、次のように言えます。
-Can you make a larger portion of this salad?
-Can you make the salad a large potion?
（サラダを大盛りにしてもらえますか）
Could you make a salad in a large bowl?
【訳】ラージサイズのサラダを作っていただけますか？
Could you 〜は Can you 〜よりも丁寧で相手の状況を伺うような言い回しになります。大体の人はこれで察するはずですが、もしかしたら大きい皿に普通盛りのサラダを入れてくる人もいるかもしれません…
Can you make an extra-size salad?
【訳】特別サイズのサラダ作れますか？
Could you 〜の方が丁寧なのは確かなのですが、もうすでに頼んでいる言い方です。
Can you〜だと、頼む以前に純粋に可能かどうかをきいている感じがします。「できない」と言われたらそれまでという。
Portion sizes are important in restaurants, you could ask for a portion of fries or a bigger portion or soup OR you could ask for a bigger portion of salad. Portion means how much you get. So ordering a large portion of fries will get you enough fries to feed a small family.
Asking for a large salad would also be enough, this is the easiest way to ask.
レストランでは "portion sizes"（一人前の量）が重要です。
例えば、
"a portion of fries"（一人前のフライドポテト）
"a bigger portion of soup"（スープの大盛り）
あるいは、
"a bigger portion of salad"（サラダの大盛り）
をお願いできます。
"portion" は一人前の量をいいます。
"a large portion of fries"（フライドポテトの大盛り）を注文すれば、小さな家族で食べられるくらいの量になります。
また、単に "a large salad"（サラダの大盛り）でも問題ありません。これが最も簡単な言い方です。
Would I be able to order a larger salad? I'm happy to pay extra.
This answer is possibly the best and most polite way of asking a waiter or waitress if you can order a larger portion of salad. In most cases a chef will be more than happy to accommodate your request, and of course as a customer because you are receiving more of something you should have to pay for. Instead of the server telling you this, it is polite to offer beforehand.
If you haven't ordered the salad yet, then you could simply order the salad by saying you want a large one "Could I get a large salad?"
If you have already placed your order and you have a change in mind for the size of the salad then you could refer to the salad by saying "that" and say "could you make that a large salad?"
Another common way of saying you want a bigger size or portion is by using the word "upsize". Upsizing means to make bigger, like an upsized drink or box of popcorn, or in this case bowl of salad.
まだサラダを注文していないなら、シンプルに「大盛りでください」と言えます。
"Could I get a large salad?"（サラダを大盛りでお願いできますか）
注文をした後気が変わってサラダのサイズを変えたいなら、サラダを "that" で表して次のように言えます。
"Could you make that a large salad?"（サラダを大盛りにできますか）
また、"upsize" という言葉もよく使われます。"upsize" は「〔ドリンク・ポップコーンなどを〕より大きなサイズにする」という意味です。この場合は、「サラダのサイズ」について言っています。
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