I have no problem (爬)the mountain,which is not too high.
It's possible for people to live to be more than one (世纪).
Don't swim in the river.It's (危险的) for you.
The (人口) of China is about 1.41 billion in 2021.
Many people think computers and the Internet will (取代) books.
They'd like to go sightseeing (而不是) of staying at the hotel.