下の解答でいかがでしょうか?
1.salt (4)a pinch of...
2.soap (3)a cake of...
3.oil (2)a can of...
4.dust (5)a trail of...
5.kindness (1)an act of...
1.I've had (so many kindnesses) show to me by the faculty.
(4)抽象名詞の普通名詞化
2.(The jury) are considering their verdict.
(3)集合名詞の複数扱い
3.(A Mr. Borg) telephoned.
(2)固有名詞に不定冠詞を付ける用法
4.Some parents believe (a boy) must learn to stand up and fight like a man.
(5)普通名詞の総称的用法
5.What are your (politics)?
(1)学問の名前を複数扱いする用法
お礼
早速のご連絡をいただき、ありがとうございました。