Mike went boating with his friends last weekend. They ______ a good time.
—Can I get you a cup of black coffee?—______.
—I prefer at home on such a rainy day. —So do I.
A low-carbon(低碳) lifestyle has an effect our daily life. People are paying more and more attention to energies these days.
These pictures will show you____.
—Don’t play with the knife, ______ you’ll cut your hand. —Sorry, I ______ .