- Generally speaking, every written sentence needs a subject.
- When you combine two independent sentences with a coordinating conjunction (e.g., and, or, but), repeating the same subject might appear redundant.
- Whenever the message of the sentence is unambigious, you can leave out the subject in the second part of your phrase.
The connectors and, or, but, and then combine two main clauses into one sentence. In order to be as least redundant as possible, it’s possible to drop the subject—in the second main clause. We explain when you should avoid doing this, and when omitting the subject is the better alternative.
Subject Dropping Not Possible
If the subject of the first clause is a compound subject, and the only one of that group is the subject of the second clause, then you cannot drop the subject. Thus, you need to specify who (of that group) is the subject of the second clause. For example, if you mean to write:
The parents, the kids, and the dog went on vacation and the kids got a sunburn.
Then you need to write the full thing out, you cannot drop the subject and write:
The parents, the kids, and the dog went on vacation and [Ø] got a sunburn.
Because then, it reads as if everyone got a sunburn.
If a sentence consists of two clauses with different subjects, remember not to drop the second one. In the following example, you can see how doing so makes the sentence ambiguous. You would guess that the students were the subjects of both clauses.
The students can’t go to university while [the professors are] striking next week.
The students can’t go to university while [Ø] striking next week.
Subject Omission Only in Informal Writing or Speech
In casual conversation, we often leave out words, or even whole phrases. We especially like to drop auxiliaries, copula verbs (e.g., to be), and relative pronouns, when the resulting sentence is still comprehensible. And then, we might also omit subjects or objects of sentences. Most of the time, the personal pronoun “I” gets elided at the beginning of a sentence.
- [Have you] ever been to Paris?
- [Are they] still playing?
- [I] love you.
- [I] haven’t been to Paris yet. [I’m] going this summer.
Our advice is to write everything out in full, as these constructions are highly context-dependent, and because many people consider them to be informal and colloquial.
Omitting the Subject in Formal Writing
Gerund constructions in formal writing provide the option to not repeat an identical subject. You can find these in subordinate clauses introduced by while, as, when, etc.
The man got a cramp while [he was] swimming in the sea.
The constructions mentioned above (with and, or, but, and then) also facilitate an omission of the subject when modal verbs come into play. Nevertheless, this second subject must always be the same as the first one.
They finished early and they could have come sooner.
→ They finished early and [Ø] could have come sooner.
Dropping or not dropping the subject is a stylistic choice, as both are grammatically correct. LanguageTool strongly encourages dropping redundant subjects whenever possible to ensure a precise and clear tone in your writing. It corrects traditional mistakes, [Ø] suggests improvements, and [Ø] proposes synonyms.
- Never omit the second subject when it’s not the same as the first one.
- Never omit the second subject when the resulting sentence is ambiguous.
- Always omit the second subject when it’s the same as the first one.
- Omitting the first subject is highly informal and only used in spoken language.