以通用規則來看，代名詞應該指涉單一、明確描述的先行詞，並且應該保持與先行詞在數量上的一致性。在我個人的學術編輯生涯中，幾乎每一篇文章都會遇到違反此特定規則的狀況，舉例如下：
The ZnO peaks for the samples that were dried for 5 days are smaller than that for the sample that was dried immediately.
單數的指示代詞「that」前面必須有單數的先行詞，但是上面的句子並沒有包含單數名詞。該作者明顯將「that」用來指涉「ZnO peak」，這個詞隱含在句子裡，但不是直接而明確地呈現出來，所以有時並不容易判別，因此可以修改如下：
The molar ratio in these complexes was smaller than those in the previously synthesized complexes.
此句中，作者使用複數指示代詞「those」指涉其所隱含的「molar ratios」，但是有些讀者可能會誤解，將「those」誤解為較靠近的複數名詞「complexes」。幸好，有個簡單的方法可以修正這類句子─將代詞用合適的名詞或名詞短語取代：
The molar ratio in these complexes was smaller than the ratios in the previously synthesized complexes.
還有三個額外的例句：
原句：
The line shape of the band of the heterotrinuclear complex was intermediate between those of the homotrinuclear complexes.
修改後：
The line shape of the band of the heterotrinuclear complex was intermediate between the line shapes of the homotrinuclear complexes.
原句：
In the homozygous mutant seeds, the fluorescence intensity in the rER was as weak as those in the amyloplasts.
修改後：
In the homozygous mutant seeds, the fluorescence intensity in the rER was as weak as the intensities in the amyloplasts.
原句：
The massic activities of 210Pb in soils, fly ash, and coal were compared with that in aerosols.
修改後：
The massic activities of 210Pb in soils, fly ash, and coal were compared with the massic activity in aerosols.
在學術寫作裡，清晰的表達又能兼顧簡潔是很重要的。
