These questions sound very interesting. Which of the following is correct for the underlined word

Social and cultural activities for senior citizens ______ over the past several years.

I have ___rules in my home. What can I do——You can talk with your parents.

_____ the city’s public school system should be opento the children of migrant workers has become the focus of discussion.

Housing prices ______ much higher now if the government hadn’t taken measures to control housing dealing.[ ]