They ________ to enter the building by the back door; however, the front door was locked

the instructions on the packet when you take the drug and the drug, I think, will work soon.

．In the job interview, all the applicants are judged _______ their educational background and working experience

Hong Kong’s Occupy Central protesters(抗议者）______ roadblocks on the main roads and they brought trouble to the public.

_______do you have an art festival in your school—Once a year.