Jake _____his key in the office so he had to wait until his wife _______ home.

Our teacher told us light (光) _________ much faster than sound .

Danny wants to put a big star _____ the Christmas tree.[ ]

Do you know___________ in Ya’an? — On the 20th of April，2013.

_______ do you have a Music Festival at your school?—Once a year.[ ]