Helen devoted herself _______ to her research and became a top scientist in the field of applied physics.
A. seriously B. extremely C. entirely D. strictly
Vitamin D helps our bodies make a special chemical，and this special chemical，
__________，affects our brains，making us feel happy.
A. in turn B. in particular C. in advance D. in short
Everyone must have known the death of the waitress，________?
A. must they B. mustn't they C. haven't they D. have they
----Tony is such a selfish person.
----I agree. Never again _________ with him.
A. 1 will deal B. I do deal C. will I deal D. do I deal
After driving for 20 miles，Jackson realized that he _______ in the wrong direction.
A. was driving B. drove C. had been driving D. had driven
---Do you think it wise for Chinese parents to try to do everything for their children?
---No, that’s ________ they are mistaken.
A. when B. where C. what D. how
