they say there are sever tests? several?? seven?? ?

Please read the statement carefully!!!

“They are sever test cases ！！！ please learn better English!!! //no offending sever [英]'sevə(r) [美]ˈsɛvɚ vt. 分离或分开;切制;分离：断决（例如，关系） vi. 切开：切开或打开;分开：相互分开或分离 [例句]But personalised filters sever the synapses in that brain. 但是个性化过滤，切断了突触的大脑。

Several. So sorry!!

Anytime:)