There be pork and beef 中be是are还是is

There be pork and beef 中be是are还是is Pork and beef ____ meat.答案是is还是are? there be句型中后面是不可数名词复数,前面是there is还是there are? there be a group of people中be是is还是are? there is some beef还是there are some beef There be 结构中不可数名词用are 还是is be a group of 中be是is 还是are? there _ a rich man and his daughter到底该is 还是 are?按理说there be 请问：当there be 句子中出现NO时,BE应该用is还是are? 一下句子there be 结构 中be应该是is 还是 are 窗帘这个单词curtain用There be句型表述是用there is 还是there are there be句型中的be用is还是are,是根据哪里判断?