Nowadays people are convinced ___ the negative effect of second-hand smoking ___ people around.
If ____ in, viruses can result in illness or even death.
By the 1920s, Howard Carter ____ an explorer.
Three mountains, Meili, Baimang and Haba, _____ are covered with snow, tower over the land.
Is _______ three hours _______ the poor boy to come to school on foot?
No. 1 Middle School of Anxiang is the very place ______ Song Zhenyu, the Provincial science top of Hunan in 2014, was studying.