1 My book hasn't been returned by Mary yet
2 My house is smaller than her house
3 It's difficult to find a job at my age
4 Lan is older than Mai
5 I was sent to school by my parents when i was six years old
6 It's easy to get acquainted with a regulation in a new school
7 A motorbike is more expensivethan a bicycle
8 This letter isn't written by the principle
9 It's harmful to smoke a lot
10 A birthday cake is being made in the kitchen by Mary