Imitating others’ actions in Tik Tok _____ be very dangerous, so you can’t be too careful.
A.should B.shall C.might D.can
— Why not go out to play with them?
—Sorry. I haven’t finished my homework yet, I ______ my mother in the kitchen all day yesterday.
A.have been helping B.had helped
C.was helping D.had been helping
If you are addicted to your mobile phone, that’s ______ you should lay it down and be involved in meaningful activities.
A.when B.why C.where D.how
In the library’s warehouse, robots would manage stock and fetch books ______.
A.on board B.on watch C.on demand D.on occasion
He pointed out such a crucial detail about the experiment ______ we could never neglect.
A.as B.that C.where D.when
Education reform has swept across schools, bringing with ______ new opportunities for students to develop in an all-round way.
A.one B.it C.them D.those
