.
By around 900 AD,there were many places in Northern Europe______the Vikings chose to live.
| A．in which | B．when | C．which | D．at which |
His writing is so confusing that it's difficult to make out ________ it is he is trying to express.(2011·安徽)
| A．that | B．how | C．who | D．what |
The shocking news made me realize ________ terrible problems we would face.(2011·北京)
| A．what | B．how | C．that | D．why |
As many as five courses are provided，and you are free to choose ________ suits you best.(2012·陕西)
| A．whatever | B．whichever | C．whenever | D．wherever |
________ wants to stay in a hotel has to pay their own way.
| A．Anyone | B．The one | C．Whoever | D．Who |
It was never clear ________ the man hadn't reported the accident sooner.(2011·江苏)
| A．that | B．how | C．when | D．why |