Ordinary soap, _________ correctly, can deal with bacteria effectively.
used
to use
using
use
They must have been enjoying themselves there,or they __________ so long.
Eye doctors recommend that a child's first eye exam ________ at the age of six months old.
—Where are the children? The dinner's going to be completely ruined. —I wish they______always late.
George is going to talk about the geography of his country, but I'd rather he ________ more on its culture.
— The professor gave a really good speech. — I suggest you _____ him some specific questions about his work experience.