Corveus lacks 6 - 4 = <<6-4=2>>2 hours of sleep every day.

Therefore, Corveus' total hours of lack of sleep every week is 2 x 7 = <<2*7=14>>14.

# Answer

14
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Corveus sleeps 4 hours a day and his doctor recommended for him to sleep 6 hours a day. How many hours of sleep does Corveus lack in a week?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
14
Corveus sleeps 4 hours a day and his doctor recommended for him to sleep 6 hours a day. How many hours of sleep does Corveus lack in a week?
train