1.The museum offer us (a large collection of ) examples of antigues in ancient times.
2.Niagara Falls (attracts) millions of visitors because of its beautiful scenery.
3.The person at this number isn't (available) to take your call,please leave a message.
4.I am sorry to say that a bad cold (keeps) me (a prisoner) to my room.
5.The doctors are performing the opetation on the patient in order to (remove) cance from his stomach.
6.The (surprising) numbers of the plants are recorded on cards so that people can know what they actually are.