напиши три вопроса чтобы узнать сколько у твоего одноклассника в саду скамеек, деревьев, цветов
how many
how
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How many benches do you have in your garden? How many trees do you have in your garden? How many flowers do you have in your garden? Я бы так написала)

How many benches in your garden? How many trees in your garden? How many flowers in your garden?