Составить предложение со словом had

you mustn't open the door for a stranger. a stranger should trick you. you might answer the phone. you don't have to tell everybody that you are home alone . you must know your parents' phone number. it have to be wise to know your neighbours .

everyone agrees that unless tiger population is protected ,they will become extinct.if it were not the efforts made by international campaigns the extinction would already have become a fact.it is time to cooperate and help to animals otherwise the future will be sad.supposing there were no tigers left in the world: how would we all feel? !