a.  a part of= part of （part 永遠(yuǎn)對）

例題：

Canadian scarlet-clad (guards) and Mounties (with) horseback are (part) of the (summer scene) in Ottawa.

答案: B  withàon

b. 表示職務(wù)、身份、親屬關(guān)系的詞可以單獨使用（a founder 的a 可省略，也可加the）

eg: Little Bush, son of George Bush, is running for the office of president. √

is chief of the Miami tribe √

Allan Pinkerton, (founder) of (the famous) detective agency that bears (him) name, directed a Civil War espionage間諜 system (behind) Confederate lines.

答案: C  himàhis

c. in + 單數(shù)名詞 “在某一方面，領(lǐng)域”

in function, in size, in color, in shape, in stage, in medical science

d. 表示“種類”名詞后所接noun可單獨使用

eg: each type of/ kind of/ sort of/ category of shoe

each category of shoes 復(fù)數(shù)也對，但單數(shù)更好

e. 固定詞組中的名詞不要改變：in honor/ danger of, in response to