Adding extra information to a sentence without making it awkward or confusing is a skill that transforms your English from basic to polished. Understanding how which and that work as relative pronouns for animals, things, and concepts allows you to combine two ideas into one clear, natural sentence.
How do which and that add extra information to sentences?
When you have two separate ideas and want to merge them, which and that act as bridges. For example, if you want to say "the racehorse is retiring" and also mention "the racehorse turned five years old," you can combine them: "The racehorse, which turned five years old, is retiring" [0:25].
The word which tends to be slightly more formal, while that is common in everyday speech. Both are correct, and the choice depends on tone. You could equally say: "The racehorse that turned five years old is retiring" [0:52].
Here are more examples that show this pattern:
- "My book, which I wrote last year, is finally getting published" [2:13].
- "My trip, which I had already packed for, was canceled" [2:40].
- "My company that I just started working for is filing for bankruptcy" [3:13].
Can you use who instead of which for animals?
When you feel a strong personal connection to an animal, using who becomes acceptable. For instance, instead of saying "My dog, which I adore, always looks so sad," you can say "My dog, who I adore, always looks so sad" [1:44]. This reflects how many speakers treat pets as family members rather than objects.
What is the correct sentence structure when using which or that?
The extra information introduced by which or that must be placed in a position where, if removed, the remaining sentence still makes complete grammatical sense. This is the golden rule.
Why does word order matter so much?
Consider this incorrect attempt: "My job, which is making me crazy, I love." If you remove the which clause, you get "My job I love," which is not a proper sentence [3:55]. The correct version is: "My job, which I love, is making me crazy."
The same principle applies to other contexts:
- Correct: "The university, which I graduated from, was on the news" [4:18].
- Incorrect: "The university, which was on the news, I graduated from" — removing the clause leaves "The university I graduated from," an incomplete sentence [4:35].
When can you place the comment in different positions?
Sometimes both positions work. With the sentence about family love [5:00], you can say:
- "The love from my family, which is endless, gives me strength."
- "The love from my family that gives me strength is endless."
Both versions produce complete sentences when you remove the relative clause. If taking out "that gives me strength" leaves "The love from my family is endless" — a perfectly valid sentence — then the placement is correct.
How can you practice combining sentences with which and that?
The best approach is to start with two simple sentences and test your combination by removing the which or that clause. If what remains is a grammatically complete thought, you have structured it correctly.
Keep these points in mind:
- Use which for a more formal tone.
- Use that for casual, everyday speech.
- Use who for animals you consider part of the family.
- Always verify the remaining sentence makes sense on its own.
Try combining two facts about something you care about — your favorite book, your phone, your city — and share your sentence in the comments.
