30. Only those who have experienced hardship ____ well aware of what happiness means.
| A．can they be | B．they can be | C．can be | D．they can |
—Why, this is Henry speaking.
—Oh, I’m sorry. I didn’t ________ your voice on the phone.
| A．recognize | B．realize | C．know | D．hear |
He spoke about the country as if he had been there, but ________ he had never.
| A．frequently | B．gradually | C．actually | D．finally |
Her friend did everything in his ________ to help with her business.
| A．energy | B．power | C．strength | D．force |
________ large number of people think ________ truth has been hidden on purpose.
| A．A; / | B．The; / | C．A; the | D．The; the |
This is the only way we can imagine him out of his foolish plan.
| A．persuading | B．to persuade | C．persuaded | D．persuade |