—Your brother was brave enough to tell the truth in public.
---Yes, and he will never regret_________ that. I admire him so much.
| A．to do | B．to be doing | C．to have done | D．having done |
The best way Tom thought of_________ his strength is to run for 30 minutes every day.
| A．building up | B．to build up | C．build up | D．being built up |
If we_________ sunlight_________ a dry leaf with a piece of glass, it may start burning.
| A．work; out | B．carry; out | C．focus; on | D．concentrate; on |
The government has taken a series of measures to _________ people’s needs in our country, which has provided good opportunities for many companies.
| A．explain | B．expand | C．export | D．expect |
—It’s too hot.
---Let’s open the windows to allow the air to_________.
| A．pass | B．cross | C．circle | D．circulate |