The laptop is not working because you ________ it yet.
C. hasn't charged
D. has charged
B. have charged
A. haven't charged
Dave _____Chinese for six years now. He likes it.
C. had studied
A. has studied
D. studied
B. have studied
This device _________ people to communicate by using voice commands.
B. makes
D. lets
C. applies
A. allows
Many people do not support _________on animals.
C. experiences
D. exercises
A. experiments
B. laboratories
Be careful when using electrical ________
D. exercise
C. experience
A. equipment
B. experiment
They _________ a new camera in the classroom to monitor the activities
A. installed
C. displayed
B. applied
D. charged
The company ______ introduced a new kind of smartphone since 2019. It looks fantastic!
introduce
have just introduced
introduces
has just introduced
The Internet has become a very _____ learning tool.
A. valuable
D. reliable
C. fashionable
B. comfortable