Mum, this is ________ teacher. ________ name is Li Hui.

Teenagers have all kinds of dreams. _____, some students would like to go to the moon some day. [ ]

A medicine may help with your illness, but it may make you , so you must be careful not to drive a car after taking such a medicine.

When did you become a volunteer for the elderly?– Two years ago. I ______ this group since then.

Everyone likes to buy things ________ a good price.[ ]