--- Oh, my God! My bike doesn’t work.--- Let’s _____ our parents.
—We really shouldn’t use plastic bags any more when shopping.—_____ It’s important to protect our environment.
_____he is very tired , _____he still goes on working.
When we went into the park, we saw someone _____ Chinese Kungfu.
I my homework, I guess I can't join you.
What can we students do _____ the environment?