However, there was nobody that I could ____ help.
Not only ________learn a foreign language, but also ______ master it well.
______ with a moon rover(月球车) called “Yutu” (Jade Rabbit) , Chang'e-3 successfully landed on the moon.
All their attempts to rescue the child from the burning building were _____, and he died soon.
Be careful when you cross this busy street. _____, you may get run over by a car.
Smoking is so harmful to people’s health that it kills __________ people each year than automobile accidents.