(1)要避免重復使用比較等級。如：

[誤]He is more better than before.

[正]He is much better than before.

[正]He is better than before.

(2)要避免將主語含在比較對象中。如：

[誤]China is larger than any country in Asia.

[正]China is larger than any other country in Asia.

(3)比較對像必須是同類可比較的。如：

[誤]Your computer is more expensive than Tom.

[正]Your computer is more expensive than Tom’s.

(4)最高級要注意將主語包括在比較范圍內。如：

[誤]Tom is the tallest of his three brothers.

[正]Tom is the tallest of the three brothers.

(5)要注意定冠詞在比較級中的使用。請比較：

Which is larger, Canada or Australia?

Which is the larger country, Canada or Australia?

Tom is taller than his two brothers.

Tom is the taller of the two brothers.