A.Only by installing an online classroom application do they keep track of all lessons at school.
B.By installing an online classroom application do they only keep track of all lessons at school.
C.The way they can keep track of all lessons at school is by installing an online classroom application.
D.The only way to install an online classroom application is keeping track of all lessons at school.

A.The lifeguard reminded the children to swim farther than 5 meters.
B.The lifeguard warned the children not to swim farther than 5 meters.
C.The lifeguard stopped the children from swimming farther than 5 meters.
D.The lifeguard allowed the children not to swim farther than 5 meters.

A.We last came to the national park for 3 months ago.
B.It is 3 months when we first came to the national park.
C.We haven't come to the national park for 3 months.
D.I haven't come to any national parks for 3 months.

A.She should have got more practical experiences for her job.
B.Getting more practical experiences for her job is necessary
C.She ought to get more practical experiences for her job.
D.It is possible to get more practical experiences for her job.

A.She should have got more practical experiences for her job.
B.Getting more practical experiences for her job is necessary
C.She ought to get more practical experiences for her job.
D.It is possible to get more practical experiences for her job.

A.into
B.exhausting
C.health
D.academic results

A.through
B.environment
C.are
D.his

A.play
B.to rain
C.afternoon
D.at

A.play
B.to rain
C.afternoon
D.at

A.A larger number of teens are reluctant to give others their online usernames.
B.Most teenage users agree that social media has negative consequences in their lives.
C.More than two-thirds of teens is helped online when facing challenges in their lives.
D.It is less likely that boys are going to make new relationships faster than girls.