单个名词单数变复数的特殊形式

(1) 有些以sis结尾的外来词，为ses。

e.g.diagnosis, analyasis, basis, emphasis

(2)有些外来词的单复数形式仍保留其不规则变化。

Bacterium bacteriuma,criterion,medium,datum

在结尾加a或把结尾的um变为a

⑶有些名词以改变内部的元音字母构成复数形式。

⑷某些表示生物的名词单复数同形。

⑸有些名词虽然以s结尾，但单复数形式没有任何变化。

Series/species/works/headquarters/barracks/bamboo

⑹以oo或元音字母加o结尾的词，加s。

⑺以f或fe结尾的词，有些直接加s。

Belief/chief/cliff/proof/roof/safe(保险柜)。

⑻有些由两部分组成的名词，只有复数形式。如果单独作主语，谓语动词用复数，可以用some来修饰。

Trousers/pants/socks/shorts/breaches/shoes/scissors/glasses/spectacles

⑼有些表示数量较多的名词，通常只有复数形式。

Ashes(灰尘)，remains(遗骸)，belongings(财产)，savings(积蓄)，stairs(楼梯)

Surroundings(周围的环境)

1. At least,we are required to write five theses(论文)every year.

2. There are four geese(鹅)on the lake.

3. There was (be)not a means to get in touch with those comrades on the mountains.

4. They have developed five photos(照片).

注:developed photos冲洗照片

5. He has given a series of proofs(证据)of his honesty.

6. My mother cut the cloth with a pair of(一把) scissors

注：Scissors剪刀

7. He was eager to make some extra money,since duringthese years he could hardly live on his wage(工资).