Also, Too, As Well, Either

We use also, too and as well to add extra information.

Also:

It is used more in writing than in speaking.

Like other adverbs, it is usually found before the main verb but after the verb to be.

• He took up padel last year. He also plays tennis and rugby.
• I'm off work the last week of August. I am also on holiday the first fortnight in September.
• My sister's been to Brazil. She's also been to Chile.
• Be sure to visit the Louvre. You should also go on a boat ride down the Seine.

We sometimes use it at the start of a sentence to emphasize what follows or to add a new point or topic.  

• You need to write the date at the top. Also, put your signature at the bottom of each page.
• We can talk about your ideas next week. Also, we should agree on a price.

Graham, the party who set the red lines was the UK Government (such as no FoM and no ECJ control). Also, the Irish backstop was explicitly asked by the UK. Actions have consequences and the UK Government should take responsibility for this mess.

— drpasqualec 🇪🇺🇮🇹🇬🇧 (@drpasqualec) August 14, 2019

He didn't say whether he also agreed with the governement's opinion that the police acted proportionately. https://t.co/2bjrjVO8vy

— English in Madrid (@madteacher72) October 3, 2017

@joeelm2015 I walked along the cliffs with my father. It was a very nice day. I also went canoeing along the river, observing the vultures.

— English in Madrid (@madteacher72) November 1, 2015

 

Too:

We usually put it at the end of the clause.

• He plays tennis and rugby too.
• I am on holiday the first fortnight in September too.
• She has been to Chile too.
• You should go on a boat ride down the Seine too.

It can be used after the subject but this is very formal.

• I too was disappointed about the result.
• We, too, thought the reviews were overrated.

It is especially common in response to fixed expressions or responding with a single object pronoun.

• Have a nice weekend.  - You too.
• Nice meeting you.  - Nice meeting you too.
• I have to get up early tomorrow.  - Yeah, me too.

I don't know where they are from.

The ones that used to keep me awake at night when I lived in Malasaña were definitely Spanish. I suspect most of the Real Madrid supporters in your neighbourhood are Spanish too.

— English in Madrid (@madteacher72) May 4, 2019

I LOVE HOW they are known as Cayetanos (me too)
... AWARE THAT with THESE actionS, they are MAKING THINGS WORSE.
... THINGS WON'T EVER IMPROVE. pic.twitter.com/Z64YCNyATt

— English in Madrid (@madteacher72) May 16, 2020

As well:

It is more common in speaking than writing and more common than also in speaking.

It almost always comes at the end of the clause.

• He plays tennis and rugby as well.
• I am on holiday the first fortnight in September as well.
• She's been to Chile as well.
• You should go on a boat ride down the Seine as well.

• I'll have the vegetarian burger.   - Anything else?   - Yes, I'll have chips as well.
• I'll have the vegetarian burger.  -  Anything else?   - Yes, I'll also have chips.

We use as well as before a noun or a verb.

• He enjoys listening to jazz as well as classical music.
• As well as setting up his own business, he has written a book.

Either:

We use it to connect two negative ideas (with also, too and as well we can't).

• He doesn't speak German.  - I don't either. (/ Me neither.)
• He doesn't speak German.  - I also don't.
• I don't eat meat and I don't eat fish either.
• I don't eat meat and I don't eat fish as well.
• I haven't done my homework.  .- Don't worry. I haven't done it either. (/ Me neither.)
• I haven't done my homework.  - Don't worry. I haven't done it too.