Modern (医学)is developing fast.As a result,many diseases can be prevented or cured.
We are supposed to (鼓励)the young to read more books.
Keeping an English diary can help us improve our writing (能力).
This is the (第八) year for Jim Green to stay in China.
The plane flew at a (高度) of three thousand meters.
It's necessary for us to (等待) in line in public.