The grammar “so did we/so have I/so is mine, etc.” is a way of agreeing with someone else or stating that the same thing is true about someone or something else. It is used to avoid repeating a verb or phrase, especially in short responses.
For example, if someone says “I love chocolate,” you could reply with “So do I.” This means that you also love chocolate. The “so” in this sentence is used to show agreement with the previous statement.
Another example is if someone says “I have two dogs.” You could reply with “So have I.” This means that you also have two dogs. The “so” in this sentence is used to show that the same thing is true about you.
In the English Vocabulary Profile at B1,
so did we/so have I/so is mine, etc. = someone else also does something or that the same thing is true about someone or something else
For example:
A: I‘m glad you‘re back.
B: So am I, dear boy.
“So am I” in the context above means: “I’m glad I’m back too.”
Notice that ‘we’ is the most common pronoun in our search results for the most common auxiliary verbs in iWeb for:
so BE _P .
1 SO BE IT . 10934
2 SO ARE WE. 1090
3 SO ARE YOU. 867
4 SO IS HE. 284
5 SO ARE THEY. 183
6 SO WERE WE. 159
7 SO IS SHE. 148
8 SO WAS HE. 148
9 SO WAS SHE. 80
10 SO IS MINE. 78
11 SO IS YOURS. 54
12 SO WERE THEY. 50
13 SO WERE YOU. 41
14 SO BE YOURSELF . 31
15 SO IS OURS. 18
16 SO WAS MINE. 17
17 SO IS THEIRS . 13
18 SO ARE YOURS . 13
so DO _P .
1 SO DO WE. 1358
2 SO DO YOU. 954
3 SO DID WE. 305
They all knew this could happen, and so did we.
4 SO DID HE. 262
5 SO DO IT. 245
6 SO DO THEY. 236
7 SO DOES HE. 189
8 SO DID SHE. 173
9 SO DOES SHE. 140
10 SO DID THEY. 135
11 SO DID YOU. 82
12 SO DOES YOURS. 29
13 SO DO YE . 26
14 SO DOES EVERYONE. 19
15 SO DO I. 11
16 SO DID OURS. 11
so HAVE _P .
1 SO HAVE WE. 201
The kids have had a really tough year.
So have we!
2 SO HAVE YOU. 131
3 SO HAS HE. 45
4 SO HAS SHE. 28
5 SO HAVE THEY. 24
6 SO HAD SHE. 12
7 SO HAD HE. 11