麻烦大侠们看看啊!写出分析过程,

麻烦大侠们看看啊!写出分析过程,
1.It is because she is too inexperienced _____ she does not know how to deal with the situation.
A,that B．therefore
C.so that D.so
2.Tom was too exhausted to wake easily _____.
A.when once sleeping B.when once asleep
C.when he was once sleeping D.when he once slept
3.It was from Mr.Brown _____ he received an inrerest in language an finally became a linguist.
A.who B.where
C.that D.which
4.You cannot be _____ careful when you drive a car.
A.very B.so
C.too D.enough
5.Once environmental damage _____,it takes many years for the system to recover.
A.has done B.is to do
C.does D.is done
6._____ it or not ,his discovey has crested s stir in scientifc circles.
A.Believe C.To believe
D.Believing D.Believed