background是不是可數名詞

background例句：

1、He has a strong political background.

他有強大的政治背景。

2、It is wrong to differentiate between people according to their family background.

根據出身不同而區別待人是不對的。

3、With my working-class background I feel like a fish out of water among these high-society people.

我出身於工人階級,在上流社會中感到很不自在。

4、Though his background was modest, it was in no sense deprived.

儘管他家境一般，但也並不算貧窮。

5、Like a chameleon, he could merge unobtrusively into the background.

他就像一條變色龍，可以神不知鬼不覺地隱藏在背景中間。

6、In the background, in soft focus, we see his smiling wife.

在背景部分，我們可以看到他妻子面帶微笑的蒙影像。