为什么中秋节时在八月十五呢？

Why Mid-Autumn Is Celebrated at Month 8 Day 15？

这一天是，中国农历的秋天里最中间的一天。

The date of the Festival is the middle of the autumn season, according to the Chinese calendar.

For the Full Moon为了一轮满月

在农历里，每个月的15号，月亮是最圆最亮的，在中国的文化里象征着团圆，团聚。

On the 15th of the each lunar month, the moon is at its roundest and brightest, symbolizing togetherness and reunion in Chinese culture.

For Harvest Celebration庆祝丰收

八月十五这天，通常稻谷都已经成熟、收割了，所以人们把这当成庆祝丰收，和拜神、给神表达感恩。

Month 8 day 15, is traditionally the time rice is supposed to mature and be harvested. So, people take this festival as an opportunity to celebrate the harvest and worship their gods to show their gratitude.

各式月饼在英语里怎么说呢

不同的月饼，其实主要是馅儿不同：

Different moon cakes are actually different from filling.

馅儿：filling

鲜肉月饼 pork mooncake

豆沙月饼 sweet bean paste mooncake

广式月饼 Cantonese mooncake

蛋黄莲蓉 lotus seed paste with salted egg yolk

咸鸭蛋黄 salted duck egg yolk 咸鸭蛋黄

冰皮月饼 snow skin mooncake

椰蓉 coconut

五仁 five-nuts 五仁”是指花生（peanut），核桃（walnut seed），瓜子（watermelon seed），杏仁（almond），松子（pine nut）