So do i vs That makes two of us

When to use each in English, with meaning, register, and examples.

So do i

Top 2,000 (common)

That makes two of us

InformalTop 5,000 (fairly common)
Most formal: So do iMost common: So do i
 So do iThat makes two of us
Pronunciation🇬🇧 //səʊ duː aɪ//🇺🇸 //soʊ du aɪ//🇬🇧 //ðæt meɪks tuː əv ʌs//🇺🇸 //ðæt meɪks tuː əv ʌs//
MeaningI agree with what you just said.We both feel the same way.
ExampleI think this movie is amazing. So do I!I’m worried about the exam tomorrow.
RegisterNeutralInformal
How commonTop 2,000 (common)Top 5,000 (fairly common)
Collocationsagree with someone, feel the same, share the same opinionmakes two, two of us, feel the same
Common mistakes'So do I' is often confused with 'So am I' which has a different meaning., Some learners may forget to use it only in response to positive statements.Using it in a formal context where agreement should be stated more formally., Confusing it with 'That makes one of us' which indicates disagreement.
Usage notesUsed in conversation to show agreement. It can be informal among friends but is also acceptable in neutral settings.Used in casual conversations to express agreement or shared sentiment. Avoid in formal writing or discussions.

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So do i
That makes two of us

Frequently asked questions: So do i vs That makes two of us

What's the difference between So do i and That makes two of us?

So do i: I agree with what you just said. That makes two of us: We both feel the same way.

Which is more formal: So do i and That makes two of us?

So do i is the most formal of these.

Which is more common: So do i and That makes two of us?

So do i is the most common in everyday English.

Can you show an example of each?

So do i: I think this movie is amazing. So do I! That makes two of us: I’m worried about the exam tomorrow.

Can I use So do i and That makes two of us interchangeably?

Not always. So do i and That makes two of us are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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