IS 用法正确么People in Palean can cross the the river when it is covered with ice.

在Palean,人们可以穿越河流,当它被冰覆盖时.
when it is covered with ice.正确,因为是单数被动,IS没错.那这样说对么 there still have possibility to cross the river by varies methods.there isstillpossibility to cross the river by varies methods.there be 句型。there still have不能这么用，there 与have 应该不是连一起的。Fifth, a huge majority of the people （out there） still have no idea what either HD-DVD or Blu-Ray even are. "It won't be enough, there will still （have to） be more cuts, " he said.