Очень срочно нужно, поэтому даю много баллов)
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Hi!
What a cool idea to have a party for Steve! I'd love to help you out!
If I were you, I'd invite all Steve's friends from his class at school and from his football team, too. I'll send you a list of all their email addresses if you like!
Why don't you have the party on a Friday or Saturday night? It'll be tricky for everyone to come on a Thursday.
Also, don't worry about getting everythibg ready. I don't mind coming to give you a hand!
Lots of love,
Matt

Good morning!It  is magnificent idea to organise a party for Steven.I would be grateful if you allow me to help you with it.My first advise will be to invite all Stevens friends, who study with him at school and also his friends from the football team.If it is important,I will sent you their email addresses.What is the purpose of  emphatic of your decision.Why it the party couldnt be held on a Friday or Saturday?Also, your help wasnt expected.With respectMathew