——Why didn't you go to Tom's birthday party?
——Sorry, _________.
化简求值.
卯—____—____=____
直—____—____=____
土—____—____=____
永—____—____=____
已知正实数a,b,c满足a+b+c=1,1a+1b+1c=10,则abc的取值范围是____ .
欧洲最高大的山脉是( )