it is a custom in china to have some tea or other drinks before the meal isit is a custom in china to have some tea or other drinks before the meal (is served)为什么不填 will be served
问题描述：
it is a custom in china to have some tea or other drinks before the meal is
it is a custom in china to have some tea or other drinks before the meal (is served)为什么不填 will be served
答
阐述一种一般状态而已,再说了 都用了before 没见过before后面用将来式的