Henry from Holland Ameria's web site:
"Evening dress falls into two distinct categories: Formal or Smart Casual. Smart Casual can be defined as slacks and collared shirts for men and casual dresses, slacks and informal evening wear for women. T-shirts, swimsuits, tank tops and shorts are not allowed in the restaurants or public areas during the evening hours. On festive Formal evenings, ladies usually wear a suit, cocktail dress or gown and gentlemen wear a jacket and tie, dark suit or tuxedo. There are approximately two formal nights per week."
so from this I would say that a polo style shirt would be fine, you do not need long sleeves.
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