IMO规定的Inmarsat卫星覆盖区是GMDSS的（）海区。
A、A1
B、A2
C、A3
D、A4
参考答案：C
不等式（x-1）2-（x-1）（x+1）+3（x+1）>0的解集是（ ）。
After _____ seemed an endless effort, the patient was finally able to carry out _____ seemed a perfectly normal walk.
A．what ; what
B．that；that
C．which；which
D．it；it
