how to work out the difficult physics problem ,he asked the teacher for help .
| A．Not to know | B．Not knowing | C．Knowing not | D．Not known |
I said hello to you in the street yesterday, but you ________ me completely.
—I'm sorry. Maybe I didn't notice you.
| A．cheated | B．hid |
| C．ignored | D．recognized |
petrol
| A．fluent | B．destroy | C．prefer | D．spelling |
concern
| A．cartoon | B．suitcase | C．calm | D．cycle |
active
| A．stage | B．attack | C．accent | D．usage |
earthquake
| A．method | B．bother | C．breathe | D．although |