When you have reviewed enough manuscripts, you stop reading individual words and start sensing friction. Long before you can name what is wrong, you feel yourself working harder than you should, re-reading a sentence, flipping back to check what a term meant, losing the thread of an argument. And a reviewer who is working hard is a reviewer slowly losing trust in the paper.
The same handful of language patterns produce that friction, over and over, in papers by non-native English authors. None of them is a grammar disaster. Native speakers commit most of them too. But each one adds a little drag, and together they can make a careful study read like a careless one. Here are the ten I flag most often, and the fix for each. None requires elegant English, only getting out of the reader’s way.
1The sentence that carries three ideas
This is the single most common source of friction. If a sentence contains a because, a which, and a should, it is probably three sentences wearing a trench coat. Readers re-read long sentences, and every re-read costs you a little credibility. The rule of thumb: one main idea per sentence. If you need two commas to hold it together, split it.
2One concept, three names
You call it a “tumour” in the introduction, a “lesion” in the methods, and a “mass” in the discussion. You know they are the same thing. The reader does not, and a careful reviewer starts to wonder whether you mean something subtly different each time. Choose one term per concept and use it everywhere, even when it feels repetitive. Here, repetition is clarity, not poor style.
3Hedging that hedges nothing
“It is well known that…”, “plays an important role”, “has been widely studied”. These phrases feel academic and carry no information. Worse, they invite the reviewer to ask “known by whom?” or “important how?” Cut them, or replace each with the specific fact and a citation.
4The missing or extra article
“We performed analysis of the data.” “Patient was treated with the drug.” Articles, a, an, the, are the classic non-native tell. They rarely change meaning, but a page peppered with article errors tells the editor, at a glance, that the language needs work. They are worth fixing precisely because they are so visible: a fluent pass or a good tool catches almost all of them.
5Connectors on autopilot
“However”, “Moreover”, “Thus”, “Therefore”, sprinkled in to sound formal, and often pointing the wrong way. “However” promises a contrast that never arrives; “Thus” claims a consequence you did not show. Use a connector only when the logical relationship is real, and make sure it is the right one. When in doubt, delete it; the sentences usually stand fine on their own.
6Burying the verb
“An investigation of the effect was performed” instead of “We investigated the effect.” Non-native scientific writing leans hard on nominalisations (verbs turned into nouns) and the passive voice, which together drain the energy from a sentence and pad the word count. Find the action, make it the main verb, and, where the journal allows, name who did it.
7Tense that drifts
Methods and results are past: we measured, the level rose. Established knowledge is present: smoking increases risk. Your interpretation of your own data is present: these results suggest. Mixing them, especially writing your own results in the present tense, is a small thing a reviewer registers immediately. A consistent tense map keeps the whole paper steady.
8The redundant phrase
“In order to” (use to). “Due to the fact that” (use because). “A total of 120 patients” (use 120 patients). “In the present study, we” (often just we). Each is harmless on its own. Across a manuscript they form a layer of padding the reader has to wade through to reach your meaning.
9“Respectively”, and the dangling modifier
“Groups A and B received 5 and 10 mg, respectively” is fine, but “respectively” is often misused or asked to carry too much. And the dangling modifier is a quiet logic error reviewers enjoy catching: “After centrifuging the sample, the supernatant was discarded” literally says the supernatant did the centrifuging. Name the actor, or recast the sentence.
10The vague quantifier
“Significant” used to mean large rather than statistically significant. “A number of”, “various”, “several”, “substantially” standing in for an actual value. In a results section especially, replace vague quantifiers with numbers. Reserve “significant” for when a p-value or test sits behind it, otherwise you are inviting the one comment every author dreads: significant in what sense?
The thread that connects them
None of these ten is a grammar catastrophe, and you will find every one of them in papers by native speakers. What they share is a cost. Each makes the reader work a little harder, and in peer review the reader is the person deciding the fate of your paper. Fixing them will not make your science stronger. It removes the friction between your science and the person judging it, which, when the work is good, is the only thing standing in the way.