4.It would be great if you could get back in shape in time for the World Cup.
It would be great…在对话中表示“……(真是)太好了“。if you could get back...the World Cup是由if引导的条件状语从句。
You'll never be in shape until you eat less and take more exercise。
in time for sth.的意思是“及时赶上某事物“如:
I arrived just in time for the meeting.