Recent campus tragedies show that safety measures are so important that we _______ take them too seriously.

The sweater is made____cotton, and it’s made ____Shanghai.

Zhang Lin was addicted to computer games during his last year in high school , otherwise he ____________a student of Beijing University .

Wechat really makes ________ easier for people to keep in touch with each other.

The accident happened ______ a freezing winter morning.