We can ________ with each other by e-mail with the help of the Internet nowadays.
China is larger than _________ in Africa.
Mr. Li asks us to remember that __________ careful we are, _________ mistakes we will make.
----Would you like to go to the amusement park? ----If Jack does, __________.
Because of the bad weather, we have to _________ the meeting till next week.
----Whose book is this? ----It _______ our geography teacher’s. You see, his name is on it.