The Science Museum, ______we visited during a recent trip to Britain, is one of London’s attractions.
I thinkefforts we have made to constructnew DeZhou are paying off
— Do remember to charge the mobile phone 12 hours when you first use it. — ______.
While building a tunnel through the mountains, ______.
Scientists are convinced ______ the positive effect of laughter ______ physical and mental health.
In American there are more households with pets than ______ with children.