Your hands are dirty; you _____ wash them.
should
_____ you understand these instructions?
Can
You are driving too fast; I think you ______ slow down.
should
I _____ pick you up after school because I am working late tonight.
can't
_____ you play tennis when you were younger?
Could
Kate needs to go out and do more things. She _______ spend every weekend playing computer games and chatting online.
should not/ shouldn't
Jake _______ work on his computer yesterday because it wasn’t working.
could not/ couldn't
I _______ go out right now. I am doing my homework!
cannot/ can't
When you go on the Internet, there are some rules you ______ follow.
must not
should
First of all, you ________ be careful who you talk to.
should
must not
Also, you _______ only visit safe sites that your parents say are OK to go on.
must not
should
Phelps ___________ swim when he was born
can
can't
could
couldn't
Phelps couldn’t swim when he was born but he _________ swim really fast now.
can
couldn't
can't
could
Cats cam climb trees but elephants _________ do it.
can't
couldn't
could
can
He _____ use a laptop, he doesn't know how.
can't
can
She _____ send an email until yesterday.
can't
couldn't
