Please check this sentence! -Quand tu dînes au restaurant,quelle repas préfères-tu manger?

It looks good to me -- but I'll send it to our French expert, SraMcGin. She'll probably post a reply within a few hours.

Hint:

un repas

Is it ok to say ils sont des freres ? Or ils sont freres. Thank you

Connecting to what MathMate said "hint: un repas" he was trying to tell you that the sentence is supposed to be "Quand tu dînes au restaurant, quel repas préfères-tu manger?". Because quel is masculin and quelle is feminin.

The sentence you provided is almost correct, but there are a couple of corrections needed. Here's the corrected sentence:

"Quand tu dînes au restaurant, quel repas préfères-tu manger ?"

To check this sentence, we can break it down and identify the different components:

1. "Quand tu dînes au restaurant" - This translates to "When you dine at a restaurant." It introduces the time or situation.
2. "quel repas" - This means "which meal." Here, we are asking about the specific meal.
3. "préfères-tu manger ?" - This is a question asking about your preference for eating. "Préfères-tu" means "do you prefer," and "manger" means "to eat."

To answer the question, you would state your preference for a particular meal when dining at a restaurant.