### Agreement Patterns: So, Too, Neither, and Either

When someone shares a feeling or habit, we naturally want to agree with them. If your friend says, "I love pizza," you might reply, "So do I!" or "I do too." But if they say, "I don't like mornings," the rules change—you have to use negative agreement words like "Neither do I" or "I don't either." 

This challenge covers the core rules for expressing agreement in English. You will practice choosing between positive and negative agreement words (*so/too* vs. *neither/either*), matching the correct auxiliary verb (*do, be, have, can, did*), and recognizing multiple valid forms of agreement, including informal phrases like "Me neither." Along the way, you'll help terrible chefs, lazy cats, and confused detectives find common ground.

You will work through 12 questions in a mix of single-choice, multi-choice, drop-down, and drag-and-drop formats. 

Try the quiz to check your knowledge!


## Agreeing with Positive Statements
When someone makes a positive statement and you want to say that the same is true for you, you can use **So + auxiliary + subject** or **Subject + auxiliary + too**. 

The most important rule for both patterns is that you must use the same auxiliary (helping) verb that was used in the original sentence. If there is no auxiliary verb (like in the present or past simple), use *do*, *does*, or *did*.

*   "I **am** terrified of spiders." 
    ✅ "So **am** I." (or "I **am** too.")
*   "I **love** cold pizza." (Present simple = do)
    ✅ "So **do** I." (or "I **do** too.")
*   "I **can** swim."
    ✅ "So **can** I." (or "I **can** too.")

In informal spoken English, you can simply say **"Me too"** regardless of the verb tense.

## Agreeing with Negative Statements
When someone makes a negative statement (using words like *not, don't, can't, didn't*), you cannot use *so* or *too*. Instead, you must use **Neither + positive auxiliary + subject** or **Subject + negative auxiliary + either**. 

Because *neither* already contains a negative meaning, the auxiliary verb that follows it must be positive. If you use *either*, the auxiliary verb must be negative.

*   "I **don't** want to wake up early."
    ✅ "Neither **do** I." (or "I **don't** either.")
*   "I **can't** fly without a cape."
    ✅ "Neither **can** I." (or "I **can't** either.")
*   "I **didn't** understand the movie."
    ✅ "Neither **did** I." (or "I **didn't** either.")

Just like with positive statements, there is a quick, informal alternative for negative agreement: **"Me neither."**

## Common Mistakes to Avoid

The most frequent mistake learners make with these patterns is mixing up the word order after *So* and *Neither*. These words require subject-verb inversion, meaning the verb comes *before* the subject.

*   "I am exhausted."
    ✅ "So am I."
    ❌ "So I am." (This actually means "You are right, I *am* exhausted!" rather than "I am exhausted too.")

Another major trap is the "double negative" when using *neither*. Since *neither* means "not either," adding another negative word makes the sentence grammatically incorrect.

*   "I don't like garlic."
    ✅ "Neither do I."
    ❌ "Neither don't I." 

Finally, be careful not to blindly reply with "So do I" to every statement. You must listen to the specific verb the other person used. If they use the verb *to be*, a modal like *can*, or talk in the past tense, your reply must match!

*   "I **was** completely lost."
    ✅ "So **was** I."
    ❌ "So **did** I."


Basics. Agreement Patterns: So, Too, Neither, and Either

Agreeing with Positive Statements

Agreeing with Negative Statements

Common Mistakes to Avoid