The question was so difficult that （）

1、He ran so fast that he was out of（）

He ran so fast that he was out of（）AairBoxygenCbreathDwind

2、This question was （）difficult that no

This question was （）difficult that no one could answer it.AtooBveryCso

3、It was （）midnight that we removed the

It was （）midnight that we removed the trouble and went back to our cabin.AuntilBnot untilCnot beforeDnot after

4、The teacher spoke so fast that it was

The teacher spoke so fast that it was hard for the students to（）what he was saying.Atake inBtake outCtake upDtake over

5、It was so cold that they kept the fire

It was so cold that they kept the fire ______ all night.A to burnB burnC burningD burned

6、The dog's collar was so（）that it came

The dogs collar was so（）that it came off over his head.AlooseBslightCbroadDexcessive