台灣轉學考獸醫

如果東海有獸醫讀，你可以申請轉系。
但如果你由東海想轉台大或中興，咁你要同哋本地生一齊喺暑假時考插大，如果考到，咁你就可以轉校，否則你要讀番原校直到畢業為止。

You don't even know what you want, you havw to make up your mind which major you want to go for. Looks like you are going in a circle. Taiwan University, of course they teach in Chinese, Veterinarian is not a easy subject. Hong Kong do not have Veterinarian School, therefore, you are able to practice after graduated from Vet School of Taiwan. Whether you are able to transfer to Taiwan University, you have to look up their transfer requirement. The last question regarding the Enviromental Science and Engineering programme should be OK. None of the Hong Kong University offer this programme, you should be OK too, but the job market is very limited (very narrow).