Only when it rains in summer_______ such beautiful rainbows here.
Why did _____ take Aunt Alice almost an hour to get home ? —I don’t know . Maybe there was something wrong with her car .
Mr. Green didn’t understand ________ made his daughter so absent-minded this morning.
Look! Somebody_______ the sofa.—- Well, it wasn’t me. I didn’t do it.
It’s said that scientists have ________ a way to deal with the serious disease