用所给词的正确形式填空。

1. At the ______ (begin) of the meeting, Mr. Wang made a speech.

2. On both ______ (side) of the river, there are a lot of small tombs.

3. He spent two and a half ______ (day) doing the job.

4. I am looking forward to ______ (see) you again..

5. When did you start ______ (learn) English.

简述牛用抗生素的种类和使用注意事项。