Recently, I heard that one of my friends wanted to change his major after one-year learning because he found that he had no interest and motivation in learning this major. From my point of view, it is not wise to change major halfway. 
最近，我聽說我一個朋友說經過一年的學習后他想換專業，因為他發現他對現在這個專業沒有任何的興趣和動力。從我的角度來看，中途換專業是不明智的。
There are several disadvantages of changing major halfway. In the first place, changing major halfway means that we spend much time, energy and money in the last major but do not mastered the whole knowledge of that major yet. Second, changing major halfway needs a great resolution and we will face much pressure from others. Finally, changing major halfway may increase the burden of our family finance in that we need to spend another amount of money on another major. In addition, if we change our major halfway, we will lose a chance to find out our potential. Lack of persistence and willpower, we are difficult to be successful. 
中途換專業有幾點弊端。首先，中途換專業意味著我們要花更多的時間，精力和金錢在后面的專業上，卻還不能全面的掌握該專業的知識。第二，中途換專業需要很大的決心而且我們要面臨來自其他人的壓力。最后，中途換專業可能會增加我們的家庭經濟負擔，因為我們需要花另外一大筆錢在另一個專業上。此外，如果我們中途換了專業，我們就會失去一個發現我們潛能的機會。缺乏毅力和意志力是很難成功的。
In short, it is not advocated that we change major halfway. Therefore, we had better take all aspects into consideration when we are choosing major so that we can avoid change major halfway. Once we choose a major, we should try our best to learn it better.
總之，不主張中途換專業。因此，在選擇專業的時候我們最好全面考慮清楚，這樣我們就可以避免中途換專業。一旦我們選擇了一個專業，我們就應該盡最大努力把它學好。