Having trouble with grammar with these translations?

Could you please help me with these?

1 A foreigner won't be a ble to integrate (in/into) society well if he' meddles and only is willing to speak his language in the foregn counrty. (how do you say it?)

2 You have an answer to/for everything. You like to have the last word.
3 We have no surety/guarantor that we'll pay our rent. (someone who says he'll pay your rent if you don't)
4 I reduced the portions of food I gave my child as he was overweight.
5 The only peace and quiet I have get is when he's asleep or at school.
6 He holds his fork as if/like its a shovel.
7 You're supposed to stop eating before you get full.
8 Dogs have a better sense of smell than us. It's more acute.
9 He'd rather sleep anywhere but in here.
10 He' played in a movie where/in which he played the part of a killer.
11 That's what it'd cost me to buy/the amount it would cost me to buy...
12 If you look at the screen at/from an angle you'll see the fingerprints and stains.
13 Ill make it my life's mission to make sure
14 The song gets repetetive towards the end.
15 I can take 2 different routes to my house from here, either take the bus or the subway. If I had taken the bus I'd still be at the bus stop by the time I got home having taken the subway.
He's asking me to come work for him so he can get me far away from my family.

Thank you