Vowels make a huge difference in spoken language. In the above text you see some pairs with with ı-i, o-ö, u-ü and as you might have realised we have many like this. In other words, if you are using i instead ı it is likely to be another word. Smillar with o instead ö and u instead ü. In the above list harmless pairs are chooseb but in some cases you could possibly say a rude word without meaning it.
Certainly I'm not going to give examples here.

Hello tabard,
42 needs revision. One word isn't is somewhat unclear and isn't completely seperated to parts.

"Vay Vay! Pencereyi aç çok duman var." Nice sentence.
All words that have a single vowel are a syllable on their own.

Yes it work well. I cant figure out how to save it though.

yaren isn't common and I think it should be skipped by learners. Most of the Turks wouldnt understand and if they do they would misunderstand it as it sounds related to yar (lover). Just forget about this one.
Ahbap can also be skipped if you don't like a strong language.

Hi moonlotus4,

to put his nose out of joint
1. Be upset or irritated, especially when displaced by someone.
2. To affront them.
I'm not sure about this. Maybe "rezil etmek" is a good idea.
http://www.turkishdictionary.net/index.php?word=rezil

to not rub his nose in it
smillar to the next one:
"burnumdan getirme" (literally: dont make it come from my nose) dont make me regretfull of what I have done.

to rub his nose in it
"Bring something, especially an error or fault, repeatedly and forcefully to someone's attention."
http://www.answers.com/topic/rub-someone-s-nose-in-it?hl=rub&hl=nose
Burnundan getirmek: (literally: to make come it from his nose) to make someone regretful of something the person has done or said.

'soppy' as in 'soppy sentimental music'
"Aşırı duygusal" too sentimental could be used.

You could also try burun by double clicking on it. There are a few idioms of it in our dictionary.

"How are you brother?
Brother I've got a serious problem.
I'm in j-1 regarding the visa issue.
Now I need to get back the taxes I payed but I cant find Ray. You know he/she was my boss.
Could yu please find him and tell to contact me.
Here is his phone number: 123 456 789
Let's find my old boss and lets get the bucks back from the government. Thanks in advance. I'm waiting for the news."

Very good Lyndie,
I just had to remove your post becuse
sjm realised there was a phone number included accidentially. Good for you to try translations. Bye.

Meltem has already covered the main difference. There are a few details left to add.

1. dost has this meaning while arkadaş hasn't:
For a woman when you say "Onun bir dostu var" (She has a friend (dost)" you are implying that the woman is in relationship with somebody and they are not married. Could be even that one of them is married with somebody else.

2. arkadaş can be used with kız or erkek while dost cant.
kız arkadaş: girlfriend
erkek arkadaş: boyfriend

3. Dostum (not dost) is more common in daily speech. Dostum means my friend or buddy.

OK man take it easy. Tamam dostum sakin ol.
Hi, mate whats up? Selam dostum na'ber?

4. In written language arkadaşım is more common than dostum.
My dear friend,... > Sevgili arkadaşım ...

for "in, on, at" we have only one thing: the -de/-da suffix:

arabada: in the car
denizde: in the sea
masada: on the table
okulda: at school