I like math _______it’s difficult for me.A. but B. and C. or
—Have you ever _____ Mudanjiang to see the Jingbo Lake? —Yes, I have.
.—_____ you _____ your homework yet?—Yes, I _____ it ten minutes ago.
You’d better speak aloud ______ we can hear you.
—It’s very hot, but quite wet today.—_____
Now most families have only one child _____ our country’s one-child policy.