Professor Li always allows his students to voice their opinions in class, ______ sometimes their opinions are not sound

The cars give off a great deal of waste gas in the street.—Yes, But I’m sure something will be done toair pollution.

The water cool when I jumped into the pool for morning exercise.

“What did you do in the garden”“I watched my father ______ his motorbike”

Measures _____to stop housing prices from rising too fast, but it remains to be seen whether they still work.