There are a lot of people who +do ont 还是does not konw the importance of time.

There are a lot of people who +do ont 还是does not konw the importance of time.
There are a lot of people who +do ont 还是does not konw the importance of time.

There are a lot of people who +do ont 还是does not konw the importance of time.
用 do not
意为:有很多人不知道时间的重要性.

用don't, 因为people 是集体名词，通常做复数。

应该为：there are a lot of people who don't know the importance of time.who引导定语从句，先行词为a lot of people,复数意义，定语从句中谓语动词也用复数意义的

DON'T people 是复数